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Fax Celestis
2007-08-11, 04:19 PM
In Heroes of Battle, one of the spells has a material component of "ten pounds of platinum dust (500gp)."

Which sets a precedent for a pound of platinum being worth 50 gp.

Further, a platinum piece is worth 10 gp.

So that means there are 5 platinum pieces in a pound, each weighing in at 3.2 ounces (or, for the metric of you, just over 90 grams).

...that's remarkably heavy.

Arbitrarity
2007-08-11, 04:21 PM
That's a bug. All coins weigh the same (50 coins/lb), so they must have mixed up value of platinum and gold.

NullAshton
2007-08-11, 04:21 PM
That's correct. The SRD states that there are 50 coins to a pound. This is why if you have a lot of coins, you either use gems instead or have a bag of holding.

PMDM
2007-08-11, 04:24 PM
So they don't do their math. Sue them. If I was a game designer I can't be bothered to look up the exact weight of platnium. I'm worried about imbalancing an item by making it too expensive/cheap.

Or if you want an in game reason....

In the time before the elves, the dragon gods decided that since platinum was used by their enemies, they decided to make platinum universally heavier. The enemies couldn't hold their weapons to the dragons, and the dragons took over the earth. The End.

The Glyphstone
2007-08-11, 04:25 PM
Or - platinum coins just aren't pure platinum, the same way nickels today aren't pure nickel....actually, I don't know if they have any nickel at all in them...

ArmorArmadillo
2007-08-11, 04:31 PM
Or, dusting platinum isn't just a matter of hitting it with a hammer; maybe it requires a special Seal Clubber skill alchemical process to have "spell-grade" platinum dust.

Lord Lorac Silvanos
2007-08-11, 04:34 PM
They flat out state that a pound of gold is worth 50 gp and one pound of platinum is worth 500 gp.

So either platinum should be replaced with gold or ten with one.

(Source: PHB: Equipment section - Wealth Other than Coins - Table: Trade Goods)

Thanatos 51-50
2007-08-11, 04:37 PM
Minted coins, due to ease of use and gov't say-so are more valuble than pure platinum dust and/or gold bullions of the same weight.

CockroachTeaParty
2007-08-11, 04:38 PM
Perhaps the dust consists of cast off flecks and shavings of platinum deemed unworthy or making the grade into coins or jewelry?

RAGE KING!
2007-08-11, 04:38 PM
Or - platinum coins just aren't pure platinum, the same way nickels today aren't pure nickel....actually, I don't know if they have any nickel at all in them...

brilliant!


- he solved it!

PlatinumJester
2007-08-11, 04:42 PM
Hooray for Platinum :smallbiggrin:

Lord Lorac Silvanos
2007-08-11, 04:46 PM
Or - platinum coins just aren't pure platinum, the same way nickels today aren't pure nickel....actually, I don't know if they have any nickel at all in them...

They are made from a Nickel and Copper alloy.
The metal value is actually higher than 5 cents. (and no, it is not legal to melt them and sell them as metal :smalltongue: )

Dausuul
2007-08-11, 04:57 PM
Or - platinum coins just aren't pure platinum, the same way nickels today aren't pure nickel....actually, I don't know if they have any nickel at all in them...

That wouldn't solve the problem the OP was asking about; in fact it would make it worse. If a debased platinum coin weighing 1/50 of a pound, with only 10% platinum and 90% base metals, was still worth 10 gp, then ten pounds of pure platinum dust would be worth 50,000 gp.

Heroes of Battle is just wrong. Since the material component was likely balanced on cost and not weight, I'd reduce it to 1 pound of platinum dust.

ArmorArmadillo
2007-08-11, 06:31 PM
That wouldn't solve the problem the OP was asking about; in fact it would make it worse. If a debased platinum coin weighing 1/50 of a pound, with only 10% platinum and 90% base metals, was still worth 10 gp, then ten pounds of pure platinum dust would be worth 50,000 gp.

Heroes of Battle is just wrong. Since the material component was likely balanced on cost and not weight, I'd reduce it to 1 pound of platinum dust.

No, it wouldn't make it worse because the value of platinum coins doesn't derive from the inherent value of the platinum.
The coin is not "debased platinum," it is a minted coin.

Dhavaer
2007-08-11, 06:36 PM
No, it wouldn't make it worse because the value of platinum coins doesn't derive from the inherent value of the platinum.
The coin is not "debased platinum," it is a minted coin.

Actually, a pound of platinum is worth the same as a pound of platinum coins, so presumably it is derived from the inherent value of the platinum.

ArmorArmadillo
2007-08-11, 06:43 PM
Actually, a pound of platinum is worth the same as a pound of platinum coins, so presumably it is derived from the inherent value of the platinum.

Not if the most basic precepts of a currency system are in place...

Dhavaer
2007-08-11, 06:46 PM
Not if the most basic precepts of a currency system are in place...

This is D&D, the land of the ladder-to-10-foot-pole-conversion. The economic system seems to be based on 'what sounds right'.

Zincorium
2007-08-11, 06:47 PM
Just on a side note, I did some research and calculations, and if each coin of pure platinum was exactly 1/50th of a pound, they'd be slightly larger than pennies in terms of volume. Pennies would be lighter, though.

Coppers would be nearly three times as big (again assuming pure metals).

Lord Lorac Silvanos
2007-08-12, 01:56 AM
Not if the most basic precepts of a currency system are in place...

Now I am curious. What currency system do you suggest they use if coins of rare metals are not used as a store of value for the metals themselves?

Especially since they listed metal weight/value relationship match the value of the coins.

TheOOB
2007-08-12, 02:02 AM
Just on a side note, I did some research and calculations, and if each coin of pure platinum was exactly 1/50th of a pound, they'd be slightly larger than pennies in terms of volume. Pennies would be lighter, though.

Coppers would be nearly three times as big (again assuming pure metals).

WotC has already mentioned that coin weight is really low, it's a pure game mechanics thing.

You could just say that the spell requires 100 gp worth of platinum dust. When dealing with expensive material components, whats more important, the physical mass of the component, or the value associated with it? I've always thought it was the value, that way if all of a sudden a new diamond mind is found, halving the cost of diamonds, everyone wouldnt be getting raised.

Fhaolan
2007-08-12, 09:43 AM
Not if the most basic precepts of a currency system are in place...

The basic precepts of the modern script-based currency system are not the same as the basic precepts of a gold/silver-based currency system.

The process of minting a coin is to provide a governmental guarentee of the value of the coin. In a script-based currency system, what material the coin is made out is irrelevant as it is the form of the coin itself that is taken as the value. Originally, this script would be considered representing an actual value of gold kept by the government in a secure location (in America it was Fort Knox). You would then exchange between currencies based on the represented value of gold. That system has changed now, and currencies are backed purely by governmental guarentee with no gold standard backing it up. You can actually make money exchanging between currencies simply because of relative value.

In a real gold/silver-based currency system, the guarentee of minting is supposed to validate the value of the metal in the coin. This is why debased coins were such an issue, and why shaving coins was illegal. Both reduced the metal value of the coin, invalidating the guarentee. In this currency system, moneychangers would exchange coins for coins based on weight taking a service cut as profit.

Dausuul
2007-08-12, 09:57 AM
No, it wouldn't make it worse because the value of platinum coins doesn't derive from the inherent value of the platinum.
The coin is not "debased platinum," it is a minted coin.

We're not talking about a modern economy here. The value of platinum coins does derive from the inherent value of the platinum. Otherwise why would you make coins out of platinum in the first place?

The main purpose of minting coins out of precious metals, in a pre-industrial economy, is to provide a government guarantee of the coin's precious metal content. Of course, depending on the government, that guarantee may or may not be worth much; but unless there are strict price controls imposed, you're not going to see coins in such a system valued at substantially more than the value of an equivalent weight of bullion--that defeats the point of using precious metals to make your coins. If the currency is debased, the price of bullion will rise accordingly.

Edit: Ninja'd.

ArmorArmadillo
2007-08-12, 04:28 PM
We're not talking about a modern economy here. The value of platinum coins does derive from the inherent value of the platinum. Otherwise why would you make coins out of platinum in the first place?

The main purpose of minting coins out of precious metals, in a pre-industrial economy, is to provide a government guarantee of the coin's precious metal content. Of course, depending on the government, that guarantee may or may not be worth much; but unless there are strict price controls imposed, you're not going to see coins in such a system valued at substantially more than the value of an equivalent weight of bullion--that defeats the point of using precious metals to make your coins. If the currency is debased, the price of bullion will rise accordingly.

Edit: Ninja'd.
Man, then my players should really start shaving coins.

Demented
2007-08-12, 05:22 PM
Ignoring all the coin debate above...

The only problem here is that the Platinum dust in the spell's component is underpriced by a factor of 5. Assuming it requires actual platinum. Maybe they have four extra pounds of non-platinum material in their platinum dust.

Maybe they forgot that a pound of dust weighs the same as a pound of anything else.
"But dust weighs less, therefore you need more of it!"

Matthew
2007-08-12, 05:45 PM
Man, then my players should really start shaving coins.
Only works for very mundane purchases, as many vendors used Scales to validate the weight of the coins, as well as the purity.


WotC has already mentioned that coin weight is really low, it's a pure game mechanics thing.

Am I understanding you correctly? Wizards think their Coin weight estimation is low? They'd be wrong in comparison to just about any Medieval Gold Coin I can think of. Biggest ones hovered around 4 to 4.5g, as far as I am aware. D&D Gold Coins weigh about 9.0g.
They present an actual size picture of a Greyhawk Gold Coin in the PHB. Where did they mention that the coin weight is really low?

Citizen Joe
2007-08-12, 06:06 PM
Note that you can maintain the same diameter and thickness of coins if you punch a variable sized hole in the center. This allows for you to string up a length of coins for easier counting.

ranger89
2007-08-12, 07:22 PM
This is very similar to a conversation my gaming group had a couple years ago. One of the guys in the group is working towards a Ph.D. in Material Sciences (http://www.answers.com/topic/materials-science) and did some quality geeking to confirm that WotC gold per pound rule is low. According to his calculations, 10gp weighs 1lb. That would be the suck for all the obvious reasons so we decided to just stick with the RAW.

None of this makes any sense to me but in case there are science-y type people reading this thread, below are my friends calculations :smalleek: :


OK, the basic calculation is scalable WRT specific gravity, so if you take this calculation, and multiply the output by the ratio of specific gravity of gold to (silver/copper/platinum), you'll get the right answer for that type of coin, assuming they're all the same size.

Gold Piece to lb:
Density(Au)=19.32 g/cc, 1lb=453.6g, so there's 23.48cc of Au per lb

For convenience, I'm switching this over to mm3. 23480 mm3/lb.

From the PH, we measure the diameter of a gp as 31 mm, so radius 15.5, and ?*r2 gives us 754.77 mm2 for the face area of a coin.

I assumed a thickness of 3mm (about 1.5 nickels thick), giving 2264.3mm3 per coin, so....

10.37 gp/lb. and just round that to 10, since we're just making up a thickness anyway...

So yeah, it really is 10 gp/lb.

Assuming they use the same stamps for everything, and just load different slugs and dies in for different coins:
pp= 9.36/lb. call it 10.
sp=19.08/lb. call it 20.
cp=22.26/lb. call it 20

Matthew
2007-08-12, 07:33 PM
Ah, now I understand. People tried to calculate the 'real weight' of the coin from the picture? Wow! Well, you know what they say about assumptions. Obviously (and assuming that the above calculations are otherwise correct) Greyhawk Coins are only 3/5 mm thick!

technophile
2007-08-12, 07:45 PM
Man, then my players should really start shaving coins.
This is, in fact, the reason coins with milled edges were introduced as soon as technologically possible.

Edit: As well as Demented's point about merchants using scales to verify the weight/adjust for "light" coins.

Matthew
2007-08-12, 08:01 PM
Here are some actual Byzantine Coins: http://www.taxfreegold.co.uk/byzantine.html

As you can see, a Solidus of 22.5 mm Diameter weighs a mere 4.45g, Wizards are pretty much right on the money, so to speak. To nay sayers, I say, your maths is powerless in the face of fact (of course the purity of this solidus is open to question :smallbiggrin:).

Demented
2007-08-12, 10:43 PM
This is, in fact, the reason coins with milled edges were introduced as soon as technologically possible.

Edit: As well as Demented's point about merchants using scales to verify the weight/adjust for "light" coins.

That was Matthew.


Gravity in D&D is suspect anyways.

Citizen Joe
2007-08-12, 11:07 PM
Mage hand on scale...

Merchant: HOW DARE YOU TRY TO PASS OFF LIGHT COINS!
PCS: Huh? What?
Merchant: GUARDS! Seize these theives. Attempted counterfit and theft.

Tor the Fallen
2007-08-13, 01:03 AM
Not if the most basic precepts of a currency system are in place...

*Rubs hands gleefully*

You mean to tell me, in your campaign world, I can Fabricate wealth? Excellent!

Arbitrarity
2007-08-13, 09:21 AM
Major creation + Magic Aura FTW!