The price of Diamond and other materials

[Masema]

While perusing my copies of the 3.5 rulebooks, I came across a noticeable gap in the equipment and materials list.

Diamonds and other gems do not have a price per weight, for any quality of gem. Therefore, you know when you have one pound of diamonds. You know when you have 5000GP worth of diamonds. But you don't know how much that pound is worth or how much the 5000GP weighs. When you have a pound of iron, you know that it is worth 1 SP.

So, what is the weight/value ratio of diamond and other gems?

EDIT: Allow me to rephrase the question: Is there a good resource out there that has a table for weight/quality/value ratios, or anything like that?

[Manyasone]

While perusing my copies of the 3.5 rulebooks, I came across a noticeable gap in the equipment and materials list.

Diamonds and other gems do not have a price per weight, for any quality of gem. Therefore, you know when you have one pound of diamonds. You know when you have 5000GP worth of diamonds. But you don't know how much that pound is worth or how much the 5000GP weighs. When you have a pound of iron, you know that it is worth 1 SP.

So, what is the weight/value ratio of diamond and other gems?

Well, my friend. In this world a pound of diamonds is worth 56 million USD...
I believe one should say no more

[Jowgen]

I believe that when it comes to gems, the gp value depends not only on size/mass, but on things like the cut, colour and so forth. For example, according to the DMG table 3-6, red or brown-green garnet is only worth 100 gp on average, but Violet Garnet is worth 500 gp; wherein the actual value is randomly rolled.

To make things more complicated, while the max value of a Diamond according to that table is 8000 gp, there is a mention of a single diamond worth be 10.000 gp (from the Talisman of Zagyg artifact) later in the DMG.

[Âmesang]

Don't know how much it counts for, but 4th Edition's "astral diamond" is valued at 10,000 gp and weighs 1/500th lb.

Also, d20 Modern list 1 gp at $20.

[Masema]

Don't know how much it counts for, but 4th Edition's "astral diamond" is valued at 10,000 gp and weighs 1/500th lb.

Also, d20 Modern list 1 gp at $20.

So Using the d20Modern rules, a 5000 GP diamond would be worth roughly $10,000.

Then, using http://www.diamondse.info/bestdiamondprices.asp as a guide, a 5000 GP diamond is roughly 2Carats... less than an ounce. I can see know why they left the weight of diamond and gems out of the rules...

[MaxiDuRaritry]

Meanwhile, the US Dollar value of a gold piece (assuming it's mostly gold) is about $425 (http://www.giantitp.com/forums/showthread.php?295019-How-much-is-a-gold-piece-worth-in), I think. I'm pretty sure d20 Modern is off. WAAAAAY off. Unless D&D "gold" pieces are gold-foil-painted silver pieces.

[Zaydos]

So Using the d20Modern rules, a 5000 GP diamond would be worth roughly $10,000.

5000 times 20 is 100,000 not 10,000 so you're off by an order of magnitude.

That said the big value in gems in 2e and earlier was that they were negligible in weight, that 5000 GP diamond is light enough not to be worth tracking (as opposed to 1/50th of a lb like a coin).

[Masema]

5000 times 20 is 100,000 not 10,000 so you're off by an order of magnitude.

That said the big value in gems in 2e and earlier was that they were negligible in weight, that 5000 GP diamond is light enough not to be worth tracking (as opposed to 1/50th of a lb like a coin).

Indeed, I forgot how to math. Still, 20 carats is nothing.

[Remuko]

according to Manyasone and d20 modern 1 lb of diamond is worth 2.8 million GP.

[Fizban]

Meanwhile, the US Dollar value of a gold piece (assuming it's mostly gold) is about $425 (http://www.giantitp.com/forums/showthread.php?295019-How-much-is-a-gold-piece-worth-in), I think. I'm pretty sure d20 Modern is off. WAAAAAY off. Unless D&D "gold" pieces are gold-foil-painted silver pieces.
Why would you assume dnd has the same ratio of gold/people as in real life? Prices are based on value, and the amount of stuff you get for a gold piece in dnd is generally less than you'd get for $400 in real life, at least anywhere that's not a 1st world county (and quasi-medieval is not 1st world).

[MaxiDuRaritry]

Why would you assume dnd has the same ratio of gold/people as in real life? Prices are based on value, and the amount of stuff you get for a gold piece in dnd is generally less than you'd get for $400 in real life, at least anywhere that's not a 1st world county (and quasi-medieval is not 1st world).Because gold is gold. Import 1/3 of an ounce of gold into our world, and you can (currently) sell it for around $425 on the open market.

[Necroticplague]

Because gold is gold. Import 1/3 of an ounce of gold into our world, and you can (currently) sell it for around $425 on the open market.

And? The DnD world has vastly different things that would effect how valuable gold is. Currencies are only worth what they get you. And, as per the stats on gold coin weights, gold in DnD is about 1/3rd as dense as real life (in real life, given the dimensions of a GP, it should be about 15 GP to a pound). So a pound of gold in dnd world is only 1/3rd as much gold as it would be in real life.

[Deophaun]

Well, there would be no set price for "diamond," because not all diamonds are created equal. A pound of industrial grade diamonds is going to be a lot, lot cheaper than a pound of gem quality diamonds, which in turn are going to be a lot, lot cheaper than a pound of cut gem quality diamonds.

Tangentially, I'd love to see a fantasy setting where the price of diamonds was not based on the price set by a global cartel.

[MaxiDuRaritry]

And? The DnD world has vastly different things that would effect how valuable gold is. Currencies are only worth what they get you. And, as per the stats on gold coin weights, gold in DnD is about 1/3rd as dense as real life (in real life, given the dimensions of a GP, it should be about 15 GP to a pound). So a pound of gold in dnd world is only 1/3rd as much gold as it would be in real life.A gold coin weighs 1/50 of a pound (or 1/3 of an ounce), and is sized appropriately. Yes, that means that gold pieces are much, MUCH smaller than what most people visualize them as. That picture of a gold coin on page 168 of the PHB means that gold coins are razor-thin. No wonder Setzer uses them as deadly weapons.

And based on weight, a D&D gold coin currently costs about $425 IRL.

[Necroticplague]

A gold coin weighs 1/50 of a pound (or 1/3 of an ounce), and is sized appropriately. Yes, that means that gold pieces are much, MUCH smaller than what most people visualize them as. That picture of a gold coin on page 168 of the PHB means that gold coins are razor-thin. No wonder Setzer uses them as deadly weapons.
Actually, Dracomonicon gives the dimensions of the gold coin. It's a tenth of an an inch thick by slightly more than an inch across. This is why the only solution is that gold in DnD is less dense that IRL by a factor of a little more than three, because the given dimensions of the coin (.095 cubic inches), and the given weight (1/50 pounds), the resultant density of gold is .02/.095=.21 pound/cubic inch. Actual gold is .7 pounds/cubic inch.


And based on weight, a D&D gold coin currently costs about $425 IRL.
And based on what it can get you (according to the trade good tables), they're about 7 bucks (since 1 gp is also a pound of cinnamon (7 bucks), and 4 is a pig (31 bucks)).

[MaxiDuRaritry]

Actually, Dracomonicon gives the dimensions of the gold coin. It's a tenth of an an inch thick by slightly more than an inch across. This is why the only solution is that gold in DnD is less dense that IRL by a factor of a little more than three, because the given dimensions of the coin (.095 cubic inches), and the given weight (1/50 pounds), the resultant density of gold is .02/.095=.21 pound/cubic inch. Actual gold is .7 pounds/cubic inch.I suppose that answers the question of "how much of a gold piece is actual gold." At least, it can give you a rough estimate for how much copper or silver the coins are cut with.


And based on what it can get you (according to the trade good tables), they're about 7 bucks (since 1 gp is also a pound of cinnamon (7 bucks), and 4 is a pig (31 bucks)).Cinnamon and salt both were ridiculously expensive a few hundred years ago, to the point of being worth well over their weight in gold (especially the former), and now I can go to the store and buy a pound of each for a few bucks. Judging the gold value of a gold piece by what it can buy isn't at all an accurate measure by any standard, given how many factors can influence it.

[Lord Vukodlak]

Actually, Dracomonicon gives the dimensions of the gold coin. It's a tenth of an an inch thick by slightly more than an inch across. This is why the only solution is that gold in DnD is less dense that IRL by a factor of a little more than three, because the given dimensions of the coin (.095 cubic inches), and the given weight (1/50 pounds), the resultant density of gold is .02/.095=.21 pound/cubic inch. Actual gold is .7 pounds/cubic inch.
Actually Draconomicon doesn't say "gold coin" it just says a typical coin... which means either the four precious metals used in coinage all have the same density, the entry is stupid and should be ignored. Or its talking about copper coins as they'd be by far the most common and thus typical.

[Necroticplague]

I suppose that answers the question of "how much of a gold piece is actual gold." At least, it can give you a rough estimate for how much copper or silver the coins are cut with.
Given how 50 GP is a pound, and a pound of gold costs 50 GP, that seems to imply that GP are pure gold.


Cinnamon and salt both were ridiculously expensive a few hundred years ago, to the point of being worth well over their weight in gold (especially the former), and now I can go to the store and buy a pound of each for a few bucks. Judging the gold value of a gold piece by what it can buy isn't at all an accurate measure by any standard, given how many factors can influence it.

"What it buys you" is the only intrinsic value any fiat currency has. And gold is, by and by large, a fiat currency, having very few practical uses, in real life or DnD. Unless Heavy Weapons or acid-resistant armor is in high demand, gold is almost useless beyond arbitrary value as a medium of exchange. Thus, there's no reason to assume the dnd value of gold would be even remotely near it's real-life value. It could very easily be near $20 in a different world with a different history (and different sources of gold. I'm sure the Plane of Earth and Quasi-Plane of Mineral creates some downward pressure on gold's value). Not necessarily because the coin contains some lesser amount of gold, but simply because the price of gold is lower there (say, DnD world has gold's price at $1000 per pound, instead of our $18,578.80 per pound).

[MaxiDuRaritry]

Given how 50 GP is a pound, and a pound of gold costs 50 GP, that seems to imply that GP are pure gold.Not at the quoted size, they're not. Gold is MUCH denser than that, unless you can somehow fit fifty of those coins within 1.44 cubic inches? Because that's the volume of a pound of gold.


"What it buys you" is the only intrinsic value any fiat currency has. And gold is, by and by large, a fiat currency, having very few practical uses, in real life or DnD. Unless Heavy Weapons or acid-resistant armor is in high demand, gold is almost useless beyond arbitrary value as a medium of exchange. Thus, there's no reason to assume the dnd value of gold would be even remotely near it's real-life value. It could very easily be near $20 in a different world with a different history (and different sources of gold. I'm sure the Plane of Earth and Quasi-Plane of Mineral creates some downward pressure on gold's value). Not necessarily because the coin contains some lesser amount of gold, but simply because the price of gold is lower there (say, DnD world has gold's price at $1000 per pound, instead of our $18,578.80 per pound).Then it's not actually gold, as is evidenced by the above weight-to-volume conversion. It's obviously cut with a very lightweight metal of one sort or another, such as copper, to the point where its gold content is very nearly worthless.

[Necroticplague]

Not at the quoted size, they're not. Gold is MUCH denser than that, unless you can somehow fit fifty of those coins within 1.44 cubic inches? Because that's the volume of a pound of gold.
Gold in real life is denser than that. Why would you assume that gold in DnD is the same as gold in the real world? '50 GP weigh one pound' and '1 pound gold costs 50 GP' are both hard rules of the system (http://www.d20srd.org/srd/equipment/wealthAndMoney.htm).

Then it's not actually gold, as is evidenced by the above weight-to-volume conversion. It's obviously cut with a very lightweight metal of one sort or another, such as copper, to the point where its gold content is very nearly worthless.
Again, why are you assuming it's like real-life? That world simply has a lower density and value of gold than our own. A pound of gold in DnD is (a little over)three times as big as a pound of gold in real life, and valued at (a little below) 1/18th it's real life value (by weight).

[Khedrac]

Actually, Dracomonicon gives the dimensions of the gold coin. It's a tenth of an an inch thick by slightly more than an inch across. This is why the only solution is that gold in DnD is less dense that IRL by a factor of a little more than three, because the given dimensions of the coin (.095 cubic inches), and the given weight (1/50 pounds), the resultant density of gold is .02/.095=.21 pound/cubic inch. Actual gold is .7 pounds/cubic inch.
Oops, now that is interesting. An Imagine Magazine (TSR UK's magazine) article for AD&D/Basic D&D when it was 10 gp to a pound (lb) calculated that size (so a cubic foot stacked was approximately 12 by 12 by 100).
Given that the 3rd Ed coin come at 50 to the pound (lb) someone has been seriously debasing the coinage...

[Segev]

This is an area where the DM just has to make things up. He can either estimate from real-world values of diamonds (which the rest of this thread is helpful in doing), or he can simply make something up. But the rules are written to simplify it so that you only have to worry about a gold piece cost, since gold pieces are a mechanical balance-construct as much as they are a physical "thing" in the game.

Obviously, if you want to, you can tie a weight of diamond to the value, and say that weight is what's really necessary. Or that mystical qualities are brought out by polishing and cutting them, so a more expensive-cut diamond is going to be worth more gp AND worth more in spellcasting.

Obviously, if you can get it for less than it's "true" value, you shouldn't count that as reducing it, but... this really is an area of DM-call. Handle it however you like.

[MaxiDuRaritry]

Gold in real life is denser than that. Why would you assume that gold in DnD is the same as gold in the real world? '50 GP weigh one pound' and '1 pound gold costs 50 GP' are both hard rules of the system (http://www.d20srd.org/srd/equipment/wealthAndMoney.htm).

Again, why are you assuming it's like real-life? That world simply has a lower density and value of gold than our own. A pound of gold in DnD is (a little over)three times as big as a pound of gold in real life, and valued at (a little below) 1/18th it's real life value (by weight).Because if it wasn't gold, it wouldn't be gold, now, would it?

Gold is gold is gold. If it's not ~1,204 lbs per cubic foot and isn't the consistency of warm silly putty when pure at room temperature and isn't actual gold, then it's something else entirely.

Gold = gold. A = A. Reflexive property FTW.

!Gold != gold. It's not that terribly difficult of a concept, I would think.

[Necroticplague]

Because if it wasn't gold, it wouldn't be gold, now, would it?

Gold is gold is gold. If it's not ~1,204 lbs per cubic foot and isn't the consistency of warm silly putty when pure at room temperature and isn't actual gold, then it's something else entirely.

Gold = gold. A = A. Reflexive property FTW.

!Gold != gold. It's not that terribly difficult of a concept, I would think.

If we were talking entirely about the real world, I would be inclined to agree. However, we're talking about a world that doesn't operate under our rules. We're talking about a world that operates under the rules written in the books. And some of those rules are as follows:
1. A coin is slightly more than an inch in diameter, and one-tenths inches thick. (Dracominicon p.278, Sidebar 'how big is the pile').
2. 50 coins weigh a pound. (SRD, Equipment and Special Materials, Wealth and Money, Coins)
3. A pound of gold is worth 50 gold coins. (SRD, Equipment and Special Materials, Wealth and Money, Wealth other than Coins; reiterated in Dracomonicon p. 277, Coins, when it mentions trade bars)

[MaxiDuRaritry]

If we were talking entirely about the real world, I would be inclined to agree. However, we're talking about a world that doesn't operate under our rules. We're talking about a world that operates under the rules written in the books. And some of those rules are as follows:
1. A coin is slightly more than an inch in diameter, and one-tenths inches thick. (Dracominicon p.278, Sidebar 'how big is the pile').
2. 50 coins weigh a pound. (SRD, Equipment and Special Materials, Wealth and Money, Coins)
3. A pound of gold is worth 50 gold coins. (SRD, Equipment and Special Materials, Wealth and Money, Wealth other than Coins; reiterated in Dracomonicon p. 277, Coins, when it mentions trade bars)If it's gold, then it's gold, flat-out. And as stated in Core, things work like they do in the real world unless stated otherwise in the game. And since gold has the properties of gold, and we cut gold with other metals (such as copper or silver) to create coinage due to gold's super-soft nature, and it's not stated otherwise in the rules, the coins are cut with other metals to increase their durability, which is why a "gold" coin is so large, while weighing relatively little.

And the Draconomicon says "a typical coin;" it says nothing about "a 100% pure gold coin." So either a relatively pure gold coin is not "typical," or a typical gold coin is not relatively pure gold.

[Inevitability]

I believe that when it comes to gems, the gp value depends not only on size/mass, but on things like the cut, colour and so forth. For example, according to the DMG table 3-6, red or brown-green garnet is only worth 100 gp on average, but Violet Garnet is worth 500 gp; wherein the actual value is randomly rolled.

To make things more complicated, while the max value of a Diamond according to that table is 8000 gp, there is a mention of a single diamond worth be 10.000 gp (from the Talisman of Zagyg artifact) later in the DMG.

I don't think it's too weird that an artifact (the creation of which has long been lost) can have a diamond worth 25% more than your typical diamond.

[Coidzor]

If it's gold, then it's gold, flat-out. And as stated in Core, things work like they do in the real world unless stated otherwise in the game. And since gold has the properties of gold, and we cut gold with other metals (such as copper or silver) to create coinage due to gold's super-soft nature, and it's not stated otherwise in the rules, the coins are cut with other metals to increase their durability, which is why a "gold" coin is so large, while weighing relatively little.

On the other hand a pound of gold is worth 50 gp and 50 gp weighs 1 pound (http://www.d20srd.org/srd/equipment/wealthAndMoney.htm), and it's unlikely that bullion is going to be cut with the same mix as coinage.


I don't think it's too weird that an artifact (the creation of which has long been lost) can have a diamond worth 25% more than your typical diamond.

Mostly it shows that the table doesn't account for all possible values, rather than being weird, just that it's not as simple as just using the table for every purpose.

[MaxiDuRaritry]

On the other hand a pound of gold is worth 50 gp and 50 gp weighs 1 pound (http://www.d20srd.org/srd/equipment/wealthAndMoney.htm), and it's unlikely that bullion is going to be cut with the same mix as coinage.If 1.44 cubic inches of gold costs 50 gp, then whatever the gp are cut with must be just as valuable as gold in the D&D economy, just like salt is worth its literal weight in silver. Whether that same substance is just as valuable in the real world is something else altogether. I mean, if it's cut with alumin(i)um, that would make the extra mass practically worthless for us, but who knows how terribly rare alumin(i)um would be to a half-elf artificer?

[Deophaun]

On the other hand a pound of gold is worth 50 gp and 50 gp weighs 1 pound (http://www.d20srd.org/srd/equipment/wealthAndMoney.htm), and it's unlikely that bullion is going to be cut with the same mix as coinage.
Obviously they are cutting gold with mithril.
Edit:
just like salt is worth its literal weight in silver
Which should be proof enough that metal weights and values should not be taken seriously.

[Segev]

If 1.44 cubic inches of gold costs 50 gp, then whatever the gp are cut with must be just as valuable as gold in the D&D economy, just like salt is worth its literal weight in silver. Whether that same substance is just as valuable in the real world is something else altogether. I mean, if it's cut with alumin(i)um, that would make the extra mass practically worthless for us, but who knows how terribly rare alumin(i)um would be to a half-elf artificer?

Just as valuable per unit weight, at the very least, since 50 gp weighs the same as 50 gp worth of gold.

The only advantage cutting it would thus give would be, potentially, greater volume per gold piece. So less dense, but equally valuable per unit weight.

[Necroticplague]

If it's gold, then it's gold, flat-out. And as stated in Core, things work like they do in the real world unless stated otherwise in the game. And since gold has the properties of gold, and we cut gold with other metals (such as copper or silver) to create coinage due to gold's super-soft nature, and it's not stated otherwise in the rules, the coins are cut with other metals to increase their durability, which is why a "gold" coin is so large, while weighing relatively little.

And the Draconomicon says "a typical coin;" it says nothing about "a 100% pure gold coin." So either a relatively pure gold coin is not "typical," or a typical gold coin is not relatively pure gold.

If a gold coin isn't entirely gold, then why is a pound of gold coins worth a pound of gold? If the coins weren't straight gold, this would be a nonsensical trade of 1 pound gold for a variety of metals that aren't worth as much.
Also, you can't cut the coins with copper to reduce their density this much. Copper has a density of .3 lb/cubic inch, so you couldn't use it to get it down to the .21 density we have. Even zinc is .26, still too high.

Edit:
On the typicality of coins: the weight of coins and their dimensions are not specified by material. So an sp, cp, and gp are all the same size and weight . Additionally, the 50 coins:1 pound of material ratio is constant, regardless of materials (as per the trade bars in dracomonicon). To me, this seems to imply that the coins are all pure and have the same density (.21 pounds/cubic inch, which I shall note is less dense than any of the materials irl.)

[Segev]

Incidentally, a gold piece as indicated could have the same diameter as a US dime and be just slightly thicker. Not an unreasonable size for a coin, though it might be a little flimsy given the softness of gold.

[Coidzor]

If a gold coin isn't entirely gold, then why is a pound of gold coins worth a pound of gold? If the coins weren't straight gold, this would be a nonsensical trade of 1 pound gold for a variety of metals that aren't worth as much.
Also, you can't cut the coins with copper to reduce their density this much. Copper has a density of .3 lb/cubic inch, so you couldn't use it to get it down to the .21 density we have. Even zinc is .26, still too high.

Perhaps it's cut with air and thus fairly porous?

[Masema]

I love the way I ask a simple question about weight and suddenly everyone is contemplating the composition of GP and whether or not there is an alloy in the coins.

[Coidzor]

I love the way I ask a simple question about weight and suddenly everyone is contemplating the composition of GP and whether or not there is an alloy in the coins.

Well, it's an unanswerable question. Or one where the answer is, they have no weight unless assigned one, but they always have a GP value.

[Necroticplague]

Perhaps it's cut with air and thus fairly porous?

Given how much lighter these coins are than gold, that would imply 70% of its volume is air. That's less of a coin, and more of a washer.

[Segev]

Given how much lighter these coins are than gold, that would imply 70% of its volume is air. That's less of a coin, and more of a washer.

Do we have dimensions on the coins? They don't seem necessarily to be lighter than gold. If all we have is the weight and the number of gp, then we can set dimensions arbitrarily (and see if those dimensions are sensible).

I did the math yesterday: a gold piece that is 1/50 of a pound in weight, and is pure gold, can have the diameter of a US dime and be a little bit thicker than a US dime. Small, to be sure, but possibly not unreasonably so.

[Mordaedil]

Do we have dimensions on the coins? They don't seem necessarily to be lighter than gold. If all we have is the weight and the number of gp, then we can set dimensions arbitrarily (and see if those dimensions are sensible).
There is a given image of it in the PHB. The illustration also makes it look bulkier than it could be given the same things discussed here.

Of course, it could be that the markings are more valuable than the coin itself.

[Necroticplague]

Do we have dimensions on the coins? They don't seem necessarily to be lighter than gold. If all we have is the weight and the number of gp, then we can set dimensions arbitrarily (and see if those dimensions are sensible).

I did the math yesterday: a gold piece that is 1/50 of a pound in weight, and is pure gold, can have the diameter of a US dime and be a little bit thicker than a US dime. Small, to be sure, but possibly not unreasonably so.

Yes, Dracomonicon says a coin is 'a little over an inch across, and roughly one-tenth an inch thick'. So, by volume, they're roughly 4 and a half times as big as a dime. Combined with their known weight (.02 pounds) is where I've been getting a density of .21 pound/cubic inch from.

[Segev]

Hm. Counterfeiting isn't a problem, so either the coins are pure, or they're ridiculously hard to counterfeit.

Or maybe they have gems worked into them? As noted, we never get weights of gemstones for the cost, so we could arbitrarily assign that to make it work out.

[Necroticplague]

Hm. Counterfeiting isn't a problem, so either the coins are pure, or they're ridiculously hard to counterfeit.

Or maybe they have gems worked into them? As noted, we never get weights of gemstones for the cost, so we could arbitrarily assign that to make it work out.
Hmmm....some quick napkin math seems to show that a mixture of 85.3% diamond(.13pounds/cubic inch) and 14.3% gold (.7pounds/cubic inch) would have more or less the right density.Though one would have to wonder why they're then called gold coins, when diamond coins has a much better ring to it.

[Segev]

Hmmm....some quick napkin math seems to show that a mixture of 85.3% diamond(.13pounds/cubic inch) and 14.3% gold (.7pounds/cubic inch) would have more or less the right density.Though one would have to wonder why they're then called gold coins, when diamond coins has a much better ring to it.

If I'm making up a justification? Diamond dust is clear and thus only gives a "shine" or "sparkle" to the primary metal. So what we have hypothesized is a gold-mortared diamond aggregate.

[Coidzor]

And if the coins are mostly made out of diamonds, it continues the whole gems are magic while also explaining why gp is magic too.

[Klara Meison]

I'd love to know how you would manufacture that, and more importantly, why would you ever bother when a smaller solid gold coin would serve the monetary purposes just as well.

"Smaller gold density" theory makes the most sense to me.

[Segev]

Maybe they just use too much yeast when baking their coins, so they puff up more.

[Zaydos]

It was Astilabor the draconic deity of hoards. She wanted dragons to have larger hoards so willed precious metals to proliferate, unfortunately while she increased their volume she failed to think about their mass so they became less dense.

[Sandsarecool]

If a gold coin isn't entirely gold, then why is a pound of gold coins worth a pound of gold? If the coins weren't straight gold, this would be a nonsensical trade of 1 pound gold for a variety of metals that aren't worth as much.
Also, you can't cut the coins with copper to reduce their density this much. Copper has a density of .3 lb/cubic inch, so you couldn't use it to get it down to the .21 density we have. Even zinc is .26, still too high.
*snip*

Um, because you aren't buying a pound of "warm silly putty" gold, but rather a pound's worth of the standard gold coin alloy?
It never said it was pure gold. It's not entirely unreasonable to assume that bullion and coins are made of the same metal mix in a quasi-medieval setting.

[Necroticplague]

I'd love to know how you would manufacture that, and more importantly, why would you ever bother when a smaller solid gold coin would serve the monetary purposes just as well.

"Smaller gold density" theory makes the most sense to me.
You make it using magic. Wish, Miracle, Fabricate, and similar magics can create the coins (though the latter requires you to already have the gold and diamond already). I imagine the first ones would be made by a god of trade to serve as a medium, and then more get made by the Mint Planar Binding Outsiders when the need to expand the money supply comes.

You would do this for the resilience of the result. Chemically and physically, this would be something that lasts long past what most would consider forever. It would also make it hard to shave coins (too hard to me worked by most tools in a precise manner) or counterfeit (nigh-impossible to make physically). Those with the means to make decent counterfeits would have very little motive to do so (why Wish for a bunch of money when you could just Wish for what that money could get you?).


Um, because you aren't buying a pound of "warm silly putty" gold, but rather a pound's worth of the standard gold coin alloy?
It never said it was pure gold. It's not entirely unreasonable to assume that bullion and coins are made of the same metal mix in a quasi-medieval setting.

Fair enough. But in that case, what is this gold coin alloy? As pointed out in the second section of my quote, none of the normal metals you'de use in coinmaking would be light enough to get it down to the density of this alloy. Even allowing for more modern metals, the result has so little gold in it that call it a gold coin is very misleading. Some math for a gold-aluminum alloy (keeping in mind that aluminum being very cheap is a modern phenomenon) would have a properly dense alloy be about 80% aluminum, and 20% gold.

[Masema]

Maybe they just use too much yeast when baking their coins, so they puff up more.


It was Astilabor the draconic deity of hoards. She wanted dragons to have larger hoards so willed precious metals to proliferate, unfortunately while she increased their volume she failed to think about their mass so they became less dense.
These are my new head canons. Astibalor used too much yeast when baking gold for her dragon hoards.

[Extra Anchovies]

Maybe they just use too much yeast when baking their coins, so they puff up more.

:smallbiggrin::smallbiggrin::smallbiggrin:

This is, well, gold. Mind if I sig this?

[Khedrac]

These are my new head canons. Astibalor used too much yeast when baking gold for her dragon hoards.

Sounds like an answer.

[Segev]

These are my new head canons. Astibalor used too much yeast when baking gold for her dragon hoards.I like it!


:smallbiggrin::smallbiggrin::smallbiggrin:

This is, well, gold. Mind if I sig this?

I'm flattered. Go right ahead.

Also, "this is gold." I see what you did there! ;)

[KillianHawkeye]

Given how much lighter these coins are than gold, that would imply 70% of its volume is air. That's less of a coin, and more of a washer.

What, you mean like this?

http://coinquest.com/cgi-data/cq_ro/response_380/india_pice_1945.jpg

While we don't use coins with holes in the center in the United States, there is a long history of such coins in the world.

[Masema]

What, you mean like this?

http://coinquest.com/cgi-data/cq_ro/response_380/india_pice_1945.jpg

While we don't use coins with holes in the center in the United States, there is a long history of such coins in the world.

And that is also not an answer. The traditional depiction has them solid and European.

[MaxiDuRaritry]

Fair enough. But in that case, what is this gold coin alloy? As pointed out in the second section of my quote, none of the normal metals you'de use in coinmaking would be light enough to get it down to the density of this alloy. Even allowing for more modern metals, the result has so little gold in it that call it a gold coin is very misleading. Some math for a gold-aluminum alloy (keeping in mind that aluminum being very cheap is a modern phenomenon) would have a properly dense alloy be about 80% aluminum, and 20% gold.Fantasy metals work nicely in this case, since this is a fantasy world. Mithral is quite valuable, and it's hard enough to make up for gold's lack of anything resembling rigidity. Heck, it's practically a liquid.

[Necroticplague]

Fantasy metals work nicely in this case, since this is a fantasy world. Mithral is quite valuable, and it's hard enough to make up for gold's lack of anything resembling rigidity. Heck, it's practically a liquid.

1. It's valuability actually makes it's use in GP questionable. Mithral is worth 10 times it's weight in gold.
2. If you're gonna have 'fantasy metals' as an excuse for densities, why not just cut out the middleman and say gold in this world is such a fantasy metal, with much lower density?
3. Doesn't solve the 'why call it GP when it's mostly not gold' problem. Mithral is half as heavy as steel/iron, so its density is .14. Thus, 'gold coins' are 85% made out of a material that has much better practical uses , and is 10 times as valuable as gold.
And to combine 1 and 3, if you bought 1.18 pounds of this gold coin alloy (or just collected 59 GP), then separated the mithral from it (which you could easily do by melting , cooling, then cutting, due to the massive density differences), you'd end up with a pound of material that is worth 500 gp+some worthless yellow chunk left over. Or, to keep it at a single GP level, a single GP has roughly 8.5GP worth of metal in it.

[MaxiDuRaritry]

1. It's valuability actually makes it's use in GP questionable. Mithral is worth 10 times it's weight in gold.That's a good thing, in this case. Mithral is a lightweight metal, and if it's extremely valuable for its weight, and its weight is low, that means it's a viable replacement for gold if it's lightweight enough, because it would be far less dense than gold while retaining enough value that a coin made from it would be lighter than a gold coin of equal size but just as valuable.


2. If you're gonna have 'fantasy metals' as an excuse for densities, why not just cut out the middleman and say gold in this world is such a fantasy metal, with much lower density?Because gold is a thing that exists, and copping out like that is, frankly, pretty dumb. I can go find a piece of gold somewhere and show that "yes, this is gold, and no, gold does not work like that." Mithral doesn't have the same limitation.


3. Doesn't solve the 'why call it GP when it's mostly not gold' problem. Mithral is half as heavy as steel/iron, so its density is .14. Thus, 'gold coins' are 85% made out of a material that has much better practical uses , and is 10 times as valuable as gold.Its value per density is actually a benefit, as I noted above. And mithral is really only good for armor. It sucks for weaponry. And even for armor, it doesn't do that much (unless you're using it for either chain shirt or full plate), and it's not like most characters wear mithral anyway.


And to combine 1 and 3, if you bought 1.18 pounds of this gold coin alloy (or just collected 59 GP), then separated the mithral from it (which you could easily do by melting , cooling, then cutting, due to the massive density differences), you'd end up with a pound of material that is worth 500 gp+some worthless yellow chunk left over. Or, to keep it at a single GP level, a single GP has roughly 8.5GP worth of metal in it.Depends entirely on the composition, really. See above.

[Strigon]

While we don't use coins with holes in the center in the United States, there is a long history of such coins in the world.

As a Canadian, I feel obligated to bring up my favourite coin - even if I can't fathom the logic behind it.
Behold, the Toonie!
http://canadamagicshop.com/wp-content/themes/shopperpress/thumbs/dblsidetwoonie.jpg

To those who can't see it and are unfamiliar, it's a coin with a smaller coin in the middle. Why, you ask? Beats the everloving crap out of me. Seems like it would be a fairly expensive process, with a fair amount of waste - and considering we recently did away with pennies for that exact reason, I've no idea why we're still making her like this.
But I'm so glad we are.

Anyway, all that would be needed to find a suitable thing to mix gold with would be a substance with the same value per weight.

[Masema]

I think I can put this to rest now.

Gold is the size it is because a wizard did it. (http://tvtropes.org/pmwiki/pmwiki.php/Main/AWizardDidIt)

[Necroticplague]

That's a good thing, in this case. Mithral is a lightweight metal, and if it's extremely valuable for its weight, and its weight is low, that means it's a viable replacement for gold if it's lightweight enough, because it would be far less dense than gold while retaining enough value that a coin made from it would be lighter than a gold coin of equal size but just as valuable. Except the problem is, due to the ratios involved, an alloy of mithral would have far more value for it's material than for it's actual value as a GP.


Because gold is a thing that exists, and copping out like that is, frankly, pretty dumb. I can go find a piece of gold somewhere and show that "yes, this is gold, and no, gold does not work like that." Mithral doesn't have the same limitation.
Gotcha, your suspension of disbelief extends exactly as far as your knowledge. Must be physically painful to enjoy most media.
Including dnd, given how it plays so loose with basically every aspect of anything remotely scientific.

Its value per density is actually a benefit, as I noted above. And mithral is really only good for armor. It sucks for weaponry. And even for armor, it doesn't do that much (unless you're using it for either chain shirt or full plate), and it's not like most characters wear mithral anyway.
I've seen far more characters that wore mithral armor or bucklers than wielded gold weapons, and never seen anyone wear gold armor.


Depends entirely on the composition, really. See above.
And what composition do you think it can have that works? Working with the known GP density (.21), known gold density (.7), and known mithril density (.14)[half that of iron/steel], you end up with a formula for the ratios of .14X+.7(1-X)=.21. That only has one solution: x=.875. Thus, the only alloy with mithril that works is the 87.5% mixture (I was generously rounding with my 85% number earlier).

Website I've been getting real-life metal densities from. (http://www.coolmagnetman.com/magconda.htm) Other sources agree with it, that's simply the most conveniently formatted one.
GP volume: V=h(pir^2)=.1(3.14*(1.1/2)^2)=.095 cubic inches
GP weight: 1/50th pound. (given in SRD section on wealth)
GP density: .02/.095= .21 pounds/cubic inch
Iron/steel density: .28 pound/cubic inchs
Mithral: half weight of other metals. Given it's main use in weapons and armor, I assume iron/steel as a baseline.
Mithral Density: .14 pound/cubic inch
Weighted Average formula to determine density of coin given two materials: .14X+.7(1-X)
The above, to find what percentage Mithral would allow for the observed GP density:.14X+.7(1-X)=.21
Solution for that: X=.875
Note that while my decision to use 1.1 in place of 'slightly more than an inch' was arbitrary, as was my choice of baseline metal, it matters little. Even more forgiving values of 1 for diameter and .13 for mithral (half of zinc), end up with X=.79, which still has all the problems I've described before, even if of slightly less extreme magnitude. Even if Mithral is half of aluminum instead (combined with smaller coin size), that still gives us 69% mithral, which still has the problem of being worth more as scrap than money.
How much mithral would be in a given weight of this GP alloy: weight*(% mithral as decimal).
Solving for 'how much of this allows for one pound of mithral' gives:1=weight*%mithral
Solution in terms of %mithral: 1/%mithral=weight.
Since 50 gold coins is one pound, we can find the amount of gold coins that add up to an amount of GP alloy that contains one pound of mithral with this:amountcoins=50*weight=50/%mithral.
Mithral is 500 GP per pound (as per the SRD entry on it). Thus, we can find the largest % that makes it worth more as money than scrap by solving 500=50/%mithral.
The solution is .1.
Thus, any coin that's more than 10% mithral is worth more as scrap metal for the mithral alone (ignoring possible value of the gold in it). Unfortunately, even the most forgiving values of mithril percentage do not get anywhere close to this small number. Such a coin would have a density of .63, far too high for even forgivingly-calculated coin densities

[Masema]

I have noticed that most of these posts are comparing DND gold to real life gold, which is really not a good method of determining it's value. A better method would be to compare daily wages. Per the d20srd (http://www.d20srd.org/srd/equipment/goodsAndServices.htm#hirelingTrained), a trained hireling (such as a scribe) makes 3 silver pieces a day. Today, someone with the same skills makes around $9 per hour, or seventy two dollars a day. This makes one silver piece worth approximately twenty four dollars, so by daily wage, one gold piece is two hundred and forty dollars, about ten times as much as d20 modern makes it out to be.

And that's only if a trained hireling has the skills of a high school graduate. If those skills instead belong to an untrained hireling, the value triples to seven hundred and twenty dollars per GP.

[MaxiDuRaritry]

I have noticed that most of these posts are comparing DND gold to real life gold, which is really not a good method of determining it's value. A better method would be to compare daily wages. Per the d20srd (http://www.d20srd.org/srd/equipment/goodsAndServices.htm#hirelingTrained), a trained hireling (such as a scribe) makes 3 silver pieces a day. Today, someone with the same skills makes around $9 per hour, or seventy two dollars a day. This makes one silver piece worth approximately twenty four dollars, so by daily wage, one gold piece is two hundred and forty dollars, about ten times as much as d20 modern makes it out to be.

And that's only if a trained hireling has the skills of a high school graduate. If those skills instead belong to an untrained hireling, the value triples to seven hundred and twenty dollars per GP.And that has to do with the weight of gold vs its volume how? We're not comparing value vs value. We're comparing D&D gold's gross physical properties to actual gold.

[KillianHawkeye]

And that is also not an answer. The traditional depiction has them solid and European.

What exactly do you mean by "European"? :smallconfused::smallconfused:

[Khedrac]

As a Canadian, I feel obligated to bring up my favourite coin - even if I can't fathom the logic behind it.
Behold, the Toonie!
http://canadamagicshop.com/wp-content/themes/shopperpress/thumbs/dblsidetwoonie.jpg

To those who can't see it and are unfamiliar, it's a coin with a smaller coin in the middle. Why, you ask? Beats the everloving crap out of me. Seems like it would be a fairly expensive process, with a fair amount of waste - and considering we recently did away with pennies for that exact reason, I've no idea why we're still making her like this.
But I'm so glad we are.

Anyway, all that would be needed to find a suitable thing to mix gold with would be a substance with the same value per weight.
It's probably the same reasons that the UK £2 is a similar design - it is much harder to forge economically.

Forging coins isn't that hard so long as you don't mind paying more per coin than you would at the bank.
The trick for the mints is making a coin for less than its value while keeping it expensive to copy.

[Klara Meison]

For all of you saying that gold is easilly workable by hands and is "practically a liquid", can I see some sources on that? Physical properties(Young and shear modulus, tensile strength) of it I see on Wikipedia are comparable to those of steel. They are 2-3 times smaller, sure, but not a couple orders of magnitude smaller like what you seem to be suggesting.

[Fizban]

And that has to do with the weight of gold vs its volume how? We're not comparing value vs value. We're comparing D&D gold's gross physical properties to actual gold.
Which has what to do with the original question? Âmesang brought up the d20 modern conversion rate with no mention of the weight, useful as we can find diamond sizes based on real world price and convert that to gp to see what size is needed for what spells. You're the one who started complaining about that conversion rate while refusing to accept the idea that gold in dnd can't possibly be worth less than gold in our world, followed by complaining about the fact that they didn't do the research and screwed up the density. The OP just pointed out the same thing I did back on page 1 (via wages rather than goods).

You want to flood a thread with a tangent, fine. Don't tell the OP their argument is invalid when you're the one who derailed the thread.

[Inevitability]

What exactly do you mean by "European"? :smallconfused::smallconfused:

I guess the poster assumes the usual D&D coin is based on the (typically round) coins of medieval Europe? Presumably a contrast with the differently-formed coins of other, non-European cultures is deemed necessary.

Then again, I'm not that poster, so take this advice with a grain of sodium chloride.

[MaxiDuRaritry]

For all of you saying that gold is easilly workable by hands and is "practically a liquid", can I see some sources on that? Physical properties(Young and shear modulus, tensile strength) of it I see on Wikipedia are comparable to those of steel. They are 2-3 times smaller, sure, but not a couple orders of magnitude smaller like what you seem to be suggesting.http://www.open.edu/openlearn/science-maths-technology/science/chemistry/properties-gold

I've watched someone play with a few ounces of pure gold before. He left fingerprints in it when he touched it, and he left a clearly defined handprint in it when he squeezed it with some force.

[Khedrac]

http://www.open.edu/openlearn/science-maths-technology/science/chemistry/properties-gold

I've watched someone play with a few ounces of pure gold before. He left fingerprints in it when he touched it, and he left a clearly defined handprint in it when he squeezed it with some force.
Which is why no-one made coins from pure gold.

The test of biting a gold coin to check if it was real was not because you could dent gold, but because you couldn't - and you could dent lead coins...

[Klara Meison]

http://www.open.edu/openlearn/science-maths-technology/science/chemistry/properties-gold

I've watched someone play with a few ounces of pure gold before. He left fingerprints in it when he touched it, and he left a clearly defined handprint in it when he squeezed it with some force.

That site doesn't support your point. All it says about gold being soft is:

>Gold is the most malleable (something is malleable when it is easily beaten into a thin film) element there is. Just 1g of gold (the size of a grain of rice) can be beaten into a thin film covering 1 square metre.

>Gold is also extremely ductile (something is ductile when it is capable of being drawn out as a wire under tension without breaking.)

>Pure gold is also a very soft metal. It will scratch easily, and it’s therefore unsuitable in its pure state for use as coinage or jewellery. For these purposes it’s usually alloyed with other metals such as silver, copper and zinc.

All that is certainly true. It's true of pretty much any metal with low hardness. Hardness of gold is on the level of aluminium, by the way, so while it's going to be easy to accidentaly scratch (and as such be unusable as currency without alloying), it's certainly not on the level of what you are describing. If it were, those enormous gold vaults (http://www.mining.com/wp-content/uploads/2016/05/chinas-icbc-buys-giant-london-gold-vault-from-barclays.jpg) you see in the movies wouldn't be possible, since all golden bars would creep (https://en.wikipedia.org/wiki/Creep_(deformation)) and turn into pools of golden sludge within a day.

I have no idea what the person you saw was playing with, but it either wasn't gold, or he had inhuman strength.

[Masema]

What exactly do you mean by "European"? :smallconfused::smallconfused:


I guess the poster assumes the usual D&D coin is based on the (typically round) coins of medieval Europe? Presumably a contrast with the differently-formed coins of other, non-European cultures is deemed necessary.

Then again, I'm not that poster, so take this advice with a grain of sodium chloride.

Indeed. In traditional dnd illustrations, coins are shown as solid, with no hope in the center. Though evidence suggests they may be cream filled.

[Masema]

http://www.open.edu/openlearn/science-maths-technology/science/chemistry/properties-gold

I've watched someone play with a few ounces of pure gold before. He left fingerprints in it when he touched it, and he left a clearly defined handprint in it when he squeezed it with some force.

This is what is known as "Skin oil", which is also what causes fingerprints and handprints on polished steel and diamond.

[MaxiDuRaritry]

This is what is known as "Skin oil", which is also what causes fingerprints and handprints on polished steel and diamond.Ha ha. :smallannoyed: Whatever it was he was handling, he left actual indents in it, and skin oil doesn't do that.

[Segev]

Ha ha. :smallannoyed: Whatever it was he was handling, he left actual indents in it, and skin oil doesn't do that.

Not unless his is some sort of gold-etching acid, anyway.

[Inevitability]

Not unless his is some sort of gold-etching acid, anyway.

Well, the guy might've been a Xenomorph. :smalltongue:

[Masema]

Well, the guy might've been a Xenomorph. :smalltongue:

That's scary. Now I want to gate in a Hish-qu-Ten

[Thurbane]

On a related note: how much would a ruby "the size of a man's fist" be worth? It's related to a running joke in our games, but I'd love to know an answer/guesstimation!

[Necroticplague]

On a related note: how much would a ruby "the size of a man's fist" be worth? It's related to a running joke in our games, but I'd love to know an answer/guesstimation!

Ruby's density is .1452 pound/cubic inch. That's 329.31 carat/cubic inch. Price of ruby/carat can vary widely, but seemed to hover around the 2k range. So, price of diamond per unit volume is roughly 658620/cubic inch. Then, all you need to do is determine the volume of a man's hand (which I can't find) and plug it in, and you got your value. Note this assumes cost and size have a linear relation, which my gut says probably isn't true (a gem twice is big is probably a good deal more than twice as valuable), but it's mathematically convenient to make that assumption.

[Coidzor]

Ruby's density is .1452 pound/cubic inch. That's 329.31 carat/cubic inch. Price of ruby/carat can vary widely, but seemed to hover around the 2k range. So, price of diamond per unit volume is roughly 658620/cubic inch. Then, all you need to do is determine the volume of a man's hand (which I can't find) and plug it in, and you got your value. Note this assumes cost and size have a linear relation, which my gut says probably isn't true (a gem twice is big is probably a good deal more than twice as valuable), but it's mathematically convenient to make that assumption.

Well, a hand is a unit of length that's about 4 inches, right? So... 4 inches cubed or 64 cubic inches or 3.7% of a cubic foot? :smallconfused:

So something like 42,151,680 by that price per cubic inch?

[Thurbane]

So something like 42,151,680 by that price per cubic inch?

So how would that look in GP (other than a lot!).

As a sidenotes, in fantasy art (including D&D modules), gems the size of fists (or larger) actually aren't that uncommon...

[Necroticplague]

So how would that look in GP (other than a lot!).

As a sidenotes, in fantasy art (including D&D modules), gems the size of fists (or larger) actually aren't that uncommon...

Well, according to d20 modern, a GP is about 20 bucks. So, working backwards, that price in dollars is 2,107,584GP. Or, to put it another way, 42,151.68 pounds of gold coins.

[Coidzor]

In retrospect 4*4*4 may have been overly generous.

Still, even a more modest 4*3*2 is 24 for 15,806,880 and 4*3*1.5 is 18 for 11,855,160.

[Segev]

Well, we could always manufacture a ruby that size...

[Telok]

I can't help with the weights but I do have these pics sitting around.

Roman coins at the British Museum. Dime sized coins.
http://i375.photobucket.com/albums/oo198/jcc_telok/DSC02149_coins_zpsbsfnbkkz.jpg

Viking treasure at the British Museum. Wafer thin, almost foil coins.
http://i375.photobucket.com/albums/oo198/jcc_telok/DSC02144_treasure_zpsxtv7aah5.jpg

[Thurbane]

Thanks everyone for your help with the ruby - I may scale it down a little for my own game. :smalltongue:

[Segev]

Thanks everyone for your help with the ruby - I may scale it down a little for my own game. :smalltongue:

Might be wise. Ruby looks to be about 4.5 to 5.5 feet tall.

https://erstech13jsieger.files.wordpress.com/2015/01/rwby.jpg

Might be hard to fit into a setting. Easy to transport, though, as long as you keep her scythe loaded.

[Thurbane]

Strangely enough the running joke relates to a different Ruby Rose (https://en.wikipedia.org/wiki/Ruby_Rose) :smalltongue:

[DrDeth]

Here's the thing- a 5000gp diamond is whatever diamond you pay 5000gps for.

If in one area you buy a fist sized flawless blue white for 5000, and in another you buy a tiny black, flawed gem for 5000- they work the same.

[Thurbane]

OK, slightly different question - by RAW, what's the maximum value listed for a ruby?

[Inevitability]

OK, slightly different question - by RAW, what's the maximum value listed for a ruby?

There's the 1000 GP star ruby in the treasure tables.

Various spells that require rubies have material component costs exceeding this, but in such cases the rubies are always powdered.