Spell Component value

[Darth Stabber]

So animate dead requires 25gp of onyx/hd of undead. Now assuming the player of the necromancer would have a decent negotiating ability, does the 25gp mean baseline price or what they actually pay? Example lets say that you need 100gp worth of onyx for your creature, and you manage to negotiate the value of the gems down to 85gp. Does that mean you still need 15 more gp, or are you just shrewd. I am going to houserule it to being by baseline value if it's not, but I am curious as to whether or not I am deviating.

[dextercorvia]

It's a reasonable houserule, but the RAW is that it costs 25 gp with the fluff being that you use an onyx.

[Vladislav]

I believe OOTS made a joke about this once, with the spell not working properly because the caster negotiated a discount on the components. Anyway, bottom line, if it says "25 gp Onyx" it means you have to mark down 25 gp on your character sheet, no matter how shrewd you are.

[Z3ro]

It gets even worse if you find the onyx in a treasure pile. If you didn't pay for it, how do you know how much it's worth? What if two characters appraise it at different values? Better off just house-ruling it.

[Moriato]

I don't know about the DMs you've played with, but mine generally let you sell gems for their full price, like another form of currency. So getting a discount on gems would be like... buying a 1 pound bar of gold for half a pound of gold peices. Not something that a merchant would ever do.

Anyway, whenever there's a gem involved as a spell component, it's always a gem worth X amount. So it doesn't matter how much you paid for it, as long as it's worth X.

[Sacrieur]

In English (crazy how this works), 25 gp of Onyx means that you need 25 gp of Onyx. Since this is relative with haggling, this is completely bat**** insane, because it means if Onyx was really common in a particular area, and worth, say 1 gp per 5 lbs., then you would need 125 lbs. of Onyx to get the spell to work, but at the same time, in another area, where it is rare, it requires 1 gp per 1/25th of an ounce, so you'll use a single ounce of Onyx. There is no mention of which to go off of.

This violates the axiom of non-contradiction (seriously, don't violate it, because then everything just goes to hell). Because this is pretty much earth-shattering in the realm of any and all logic, and because there is a law of constant composition (which again would break D&D if violated), we can assume that playing with semantics and not allowing the caster to cast the spell only if he bought 25 gp worth of Onyx for 20 gp is completely and certifiably mad and a sign that said person is a smelly buttface.

It is safer to assume that it is just bad writing on the publisher's part, and it should read, "25 gp worth of Onyx". Since Onyx is listed at a set price in the book, this is the gold standard, and you may buy 25 gp worth of Onyx for a lower price if you're adept enough to haggle it.

[wormwood]

To further complicate things, animate dead says, "You must place a black onyx gem worth at least 25 gp per Hit Die of the undead into the mouth or eye socket of each corpse you intend to animate." This implies that it has to be a single gem. Since onyx has a book value of 50 gp according to the treasure tables, if you want more than 2 HD undead, you're out of luck.

I ran into this with my DM. He liked messing with me. I was playing a True Necromancer, so it's not like he really needed to gimp me. I did that to myself. He relented after a couple of sessions of me trying to stuff bags full of onyx into the faces of dead beasties.

[Darth Stabber]

Okay, so I'm not the only one who sees the weirdness. This comes up because I am gming for a group with a dread necro, and the dread necro is always haggling out cheaper prices on everything (she's the healer debuffer and face), and is getting animated dead soon.

Also, should I adjust treasure out put since her diplomancy is putting them ahead of wbl, or is that just a mean neutralization of a legitimate if underused skill usage. They have gotten friendly with several mechants and have one of them (and his wife) over for Kordsday supper every week. Yes, they are the friendliest tomb tainted individuals you are likely to find.

[Noneoyabizzness]

This is a point of dm ruling.

Now I would figure out son appropriate size onyx. Otherwise you will have players hoarding gems to increase value and decrease amount necessary to use.

I mean the dead don't care about the going rate.

[Darth Stabber]

You could just use carat weight. Make onyx 25gp per carat or some such nonsense. Another part of the problem is that they are from a country ruled by necromancers, and the reason they chose that region was for the bounteous onyx mines (most logical reason I could come up with to have so many necromancers in one country).

[Noneoyabizzness]

You could just use carat weight. Make onyx 25gp per carat or some such nonsense. Another part of the problem is that they are from a country ruled by necromancers, and the reason they chose that region was for the bounteous onyx mines (most logical reason I could come up with to have so many necromancers in one country).

Which means without any importing cost or scarcity, it would take alot more onyx than it would far from a mine.

[Thurbane]

I had a similar problem while running EtCR. The only trader in town puts a 50% markup on anything he sells (50% on the book price). the party needed to buy 100gp pearls for Identify. I was going to let them get away with using 67gp pearls (marked up to 100gp by the trader), but one of the party members made such a compelling case that I should be charging them 150gp, I decided to run with it. :smalleek:

[Veyr]

I had a similar problem while running EtCR. The only trader in town puts a 50% markup on anything he sells (50% on the book price). the party needed to buy 100gp pearls for Identify. I was going to let them get away with using 67gp pearls (marked up to 100gp by the trader), but one of the party members made such a compelling case that I should be charging them 150gp, I decided to run with it. :smalleek:
Hehe, as a character in an EtCR campaign whose party faced managed to get a discount from that trader (I'm pretty sure I know the one) through heavy use of Appraise, Diplomacy, Charm Person, and outright seduction, I think that ultimately that ruling is in favor of the PCs, heh.

[Sacrieur]

This is a point of dm ruling.

If a dm rules the other way I swear I will come over to his session and beat him with my logic textbook until he understands why it is a bad idea.

[tyckspoon]

For items that are used in spells, I usually just run it that the spell itself is what is setting the value of the component: 25 gp of onyx is, definitionally, the amount/quality of onyx required to Animate a 1 HD creature. Regardless of actual market price, that's what 25 gp worth of onyx is. Which means what you actually buy is Animation Stones, and you can charge whatever the heck you like for them (they're probably contraband in a lot of places, or at least considered unsavory to sell and buy.)

[supermonkeyjoe]

If there exists a large enough organisation in your campaign world then you could have the price set by them. For example in my campaign I have the price of such gems be regulated by the dwarven bankers of house Kundarak so that if you pay 100gp for a pearl with the kundarak seal of approval you know it's going to be good enough for the spell. This could also work for large institutions of mages doing similar

[Firechanter]

I have to say that we _never_ micro-managed spell components to the extent of "you need to have a Black Onyx worth 100gp". The spellcaster player simply sets aside a certain amount of their funds -- like "10.000GP in various assorted gems". Similarly, any components not stating a definite GP cost are considered "free" if you have a component pouch, and are nixed by the Eschew Materials feat.
I see how demanding to micro-manage gems allows the DM to regulate which spells can be cast how often, and might also add a bit to the fun if the spellcaster is obsessed with acquiring, say, lots of fire opals, but on the whole we never felt it was worth the bother. Maybe we'll try it in the next game.

[only1doug]

I've been considering an organisation (http://www.giantitp.com/forums/showthread.php?t=192913) designed to manipulate the concept of spell component price for awhile now, I posted it as a seperate thread to avoid de-railing this one.

Morleans Mages Emporium: An exclusive spell component shop.

To become a member you must have the eschew materials feat and pay a membership fee each year. (for which fee you will be given a order book)

all purchases can be rushed to your location, transport price included in cost of purchase.

All components without a price specified by the spell are available for 9sp, you must buy exactly 2 of these each year, no more and no less.

All material components for spells with a price in excess of 1 gp are available at standard cost but for your convenience will only be 1/10th of the normal volume associated.

simply write your order into your order book and when you have acheived the minimum order quantity your order will be sent to you. (order book is the target for the teleport spell).

[Darth Stabber]

I am probably just going to rule that all the rare gems are "worth" 25gp per carat. That way they can easily figure out how much they need for spells regardless of local economic conditions,. Worth as defined by how much certain spells want. It is really obnoxious that in the north you need more onyx to make a zombie than in the south. I need to work some stuff out for other ingredients.

[Sacrieur]

I am probably just going to rule that all the rare gems are "worth" 25gp per carat. That way they can easily figure out how much they need for spells regardless of local economic conditions,. Worth as defined by how much certain spells want. It is really obnoxious that in the north you need more onyx to make a zombie than in the south. I need to work some stuff out for other ingredients.
(emphasis mine)

Beyond obnoxious, it is completely illogical. And I don't mean illogical in the common usage, I mean illogical in the academic usage. That is to say, it completely breaks everything.

In formal logic, it would be denoted like this:

P
~P
----
Q

Where P is a premise that states onyx is worth 25 gp, and ~P means onyx is not worth 25 gp (any price except 25 gp). This is a famous logical conundrum. The end result is Q, which is ANY conclusion you want, which is chickens have red feathers. So if it is ruled semantically that you need 25 gp of onyx, then you may draw any conclusion from that, "green lollipops taste like hippos".

[Mojo_Rat]

do people really try to instill thus much realism? I'n a game. with fireballs dragons and animated corpses? the mechanics of the game set what the value of an item is. it doesn't matter where or how you acquire it hat mechanical value doesn't change.

sure my group has joked about pearl values In the desert as opposed to a tropical island but it shouldn't really leave the humor stage.


just mark off on your character shed 500 gp worth of onyx and call it a day. if you happened to pay 350 it doesn't matter so long as it's book value 500

[Darth Stabber]

do people really try to instill thus much realism? I'n a game. with fireballs dragons and animated corpses? the mechanics of the game set what the value of an item is. it doesn't matter where or how you acquire it hat mechanical value doesn't change.

sure my group has joked about pearl values In the desert as opposed to a tropical island but it shouldn't really leave the humor stage.


just mark off on your character shed 500 gp worth of onyx and call it a day. if you happened to pay 350 it doesn't matter so long as it's book value 500

Well that's the question, Rules as Written says that if you payed 350gp for the onyx than it does not count as 500. It doesn't sit well with me that the shrewd negotiating Dread Necromancer in my party need 5 pounds of onyx to make one skeleton, while if she had dumped her social skills she would need 5 ounces. (her only non-social skills are Concentration, Knowledge(religion), and 1 rank in ride).

[Sacrieur]

do people really try to instill thus much realism? I'n a game. with fireballs dragons and animated corpses? the mechanics of the game set what the value of an item is. it doesn't matter where or how you acquire it hat mechanical value doesn't change.

sure my group has joked about pearl values In the desert as opposed to a tropical island but it shouldn't really leave the humor stage.


just mark off on your character shed 500 gp worth of onyx and call it a day. if you happened to pay 350 it doesn't matter so long as it's book value 500

Do you realize that if this basic logical principle doesn't work, then all of D&D doesn't work. Sorry, as much as D&D violates the laws of physics, it cannot violate logic. If it does, it is basically an, "I win" scenario because whatever you say immediately goes (and doesn't, at the exact same time). And for the record, fireballs and undead are still logically sound.

[Veyr]

Sacrieur is right; in formal logic, you could use this situation to prove anything. There are lots of corner-cases where formal logic is not identical to reality... but this isn't one of them.

A given quantity of onyx must be sufficient for the spell or not, not yes and no at the same time.

[Kyberwulf]

You forget, that the GM sets the actual value of the gem.
All these changes to the "price" doesn't actually change the Value of the gem/ or gems set. The Changes to the "price" is due to ingame checks and blanaces.. the Actual Value doesn't really change..just the people's perception of it.



To me, its like your arguing over what temperture water boils. 100 Celsius...212 Fahrenheit....or 1,000 Chitnas..... the ACTUAL Temperture doesn't change..just the lable you put on it.

[Sacrieur]

To me, its like your arguing over what temperture water boils. 100 Celsius...212 Fahrenheit....or 1,000 Chitnas..... the ACTUAL Temperture doesn't change..just the lable you put on it.

Water boils at 0 C in a vacuum.

[Kyberwulf]

or you could counter that .. with water boils at 50 Chitnas in a vacuum....
point is..its still the same temperature,.... just..with a different name lol

[Sacrieur]

or you could counter that .. with water boils at 50 Chitnas in a vacuum....
point is..its still the same temperature,.... just..with a different name lol

The point is that water boils at different temperatures at different places.

--

It's not so much as a you say tomato and I say tomahto, this is an issue of seeing a banana and saying it is an orange.

[Mojo_Rat]

hrm let me rephrase myself ( though I thought the boiling water example was good)


the game sets book values for all items. their value I'n terms of rp or ic economics may not ever coincide with that book value)

if I find a 5000 gp ruby but the king will only give me 3000 for it. it doesn't suddenly become a 3000 gp ruby. it's a 5000 gp ruby sold for 3000.

magic items have static values that never change and no one argues it. the game says a +1 flaming burst keen rapier and a great club +2 flaming burst are worth the same and no one argues it.

all the animate dead spell cares about is the book value. what you paid for them doesn't matter. if you pay 350 gp for 500 gp I'n onyx as far as the spell cares it's 500 gp of onyx.

or do you really think I'n 3.5 that pearl size changed for identify based on location?

[olentu]

hrm let me rephrase myself ( though I thought the boiling water example was good)


the game sets book values for all items. their value I'n terms of rp or ic economics may not ever coincide with that book value)

if I find a 5000 gp ruby but the king will only give me 3000 for it. it doesn't suddenly become a 3000 gp ruby. it's a 5000 gp ruby sold for 3000.

magic items have static values that never change and no one argues it. the game says a +1 flaming burst keen rapier and a great club +2 flaming burst are worth the same and no one argues it.

all the animate dead spell cares about is the book value. what you paid for them doesn't matter. if you pay 350 gp for 500 gp I'n onyx as far as the spell cares it's 500 gp of onyx.

or do you really think I'n 3.5 that pearl size changed for identify based on location?

Oh come now it is not the size of the pearl it is location in which you use it.

Though in a more serious note as I recall the appraise skill does imply that all things have a definite value but I would have to reread the section to be sure.

[Kyberwulf]

Thank you for Proving my point further.
The point is, its still water,.. its still boiling... Your just trying to argue the that moving it around..changes it somehow

Same thing with The 25gp Onyx gem.

You can Appraise as high as you want, or as low as you want... the fact is the GM gave the Value of the Gem 25 gp. So your Appraise doesn't change the value of the gem.... just the price you charge.

the only way the Value changes on the gem,.. is if you alter it somehow... such as . with a craft (Jewelry) check... then the GM sets a new value for that Piece of Art. The Value of that Piece of Art can be appraised ... weither right or wrong of that new Value.

Same thing with the availibilty of the Materiels... just cause you have a million pounds of Onyx... the GM can make a piece of the Onyx... 25 GP. Then The price of that Onyx will go down..... not the Value on it set by the GM.

[ClockShock]

Also, should I adjust treasure out put since her diplomancy is putting them ahead of wbl, or is that just a mean neutralization of a legitimate if underused skill usage. They have gotten friendly with several mechants and have one of them (and his wife) over for Kordsday supper every week. Yes, they are the friendliest tomb tainted individuals you are likely to find.

Change 'GP price' to a weight of Onyx. Make the average/baseline price of said weight 25GP. Everyone agrees yadda yadda boring stuff about logic.

Focussing on the quote above - don't adjust treasure output. You admit it's an underused skill, so don't penalise it by turning it into a skill point drain. Doing so would just be a more complex way of coming to the same result as making her use 25GP charge rate onyx.
Even better, it sounds like the skill is being used to introduce further roleplay and plot hook opportunities - if this leads to greater wealth so be it.

[Noneoyabizzness]

If a dm rules the other way I swear I will come over to his session and beat him with my logic textbook until he understands why it is a bad idea.

Maybe the god of the dead demands tribute and if onyx happens to be cheap he wants extra

[Mojo_Rat]

it sounds to me like they are following up with the diplomacy check with lot of positive reinforcement. for the most part I think this should be fully supported.

to offset the extra wealth maybe see if you can get them to spend the extra money on mundane things. even if it's just using their merchant friends to hype up a piece of art or similar.

[Thurbane]

How about this then: the party start off in a "standard" area of the campaign world, where 25gp buy them enough Onyx for their spells. Later, the adventures carry them off to a far land, where Onyx is far more plentiful, and has a lower value. Which value do they need for their spells? The local value, or their native value?

[Mojo_Rat]

the native value is what matters for the spell. all the spell about is the universal value the books set. the local value based on availability doesn't matter.

[Safety Sword]

How about this then: the party start off in a "standard" area of the campaign world, where 25gp buy them enough Onyx for their spells. Later, the adventures carry them off to a far land, where Onyx is far more plentiful, and has a lower value. Which value do they need for their spells? The local value, or their native value?

"Damn, the exchange rate changed and now my corpses won't animate". :smallfurious:

This is the real reason necromancers are evil, they're always so angry with the stock exchange bouncing around :smallbiggrin:

[Sacrieur]

How about this then: the party start off in a "standard" area of the campaign world, where 25gp buy them enough Onyx for their spells. Later, the adventures carry them off to a far land, where Onyx is far more plentiful, and has a lower value. Which value do they need for their spells? The local value, or their native value?

/facepalm

Green lollipops taste like hippos.

[Thurbane]

the native value is what matters for the spell. all the spell about is the universal value the books set. the local value based on availability doesn't matter.
Interesting - so, say a character is born, raised and trained in the arcane arts where 25gp worth of Onyx weighs about 1 ounce.

Later, the bulk of his adventuring career takes place in a land where Onyx is much more plentiful, and 25gp would buy you about 2 ounces of Onyx. Does that mean he can cast his Animate Dead spells for half the cost of everyone else? :smalltongue:

...I think this whole topic just goes to show that real world economics and prinicples of supply & demand simply don't mesh with the D&D system. :smallfrown:

[Kyberwulf]

no,... cause apperently..the GM set the 25GP worth(as per the spell) .. at an ounce..... the Country you moved to, just gets more casting out of the their 25GPs.

[Thurbane]

no,... cause apperently..the GM set the 25GP worth(as per the spell) .. at an ounce..... the Country you moved to, just gets more casting out of the their 25GPs.
The GM also set the rate in the "new" country...

[Kyberwulf]

You said... say a character is born, raised and trained in the arcane arts where 25gp worth of Onyx weighs about 1 ounce.

he set the value of 25 GP to meet the requirements... at 1 ounce...

So the Value of the Materiels needed to satisfy the Spell's Requirements is 1 ounce. Just because you moved to another country where Onyx is cheaper.It doesn't mean that your training is canceled. or that you suddely need more onces to meet your requirements.. the only thing that changed... was the amount you SPEND per ounce.

[Epsilon Rose]

I'd like to preface what I'm about to say with the fact that I support letting materials bought at discount work as if they weren't.

The thing is, ALL of this is based on magic and depending on the fluff rules of magic in your world it could make perfect sense for it to take more onyx to raise dead in the north than the south. If magic works on consensual belief and the people (or relevant people) in an area believe a certain amount of onyx to be worth a certain value that could be what the spell cares about and what you bought it for or what people in another area believe it to be worth could be completely irrelevant.

BTW that would be more akin to the water boiling example with perceived value in place of pressure.

[Sacrieur]

I'd like to preface what I'm about to say with the fact that I support letting materials bought at discount work as if they weren't.

The thing is, ALL of this is based on magic and depending on the fluff rules of magic in your world it could make perfect sense for it to take more onyx to raise dead in the north than the south. If magic works on consensual belief and the people (or relevant people) in an area believe a certain amount of onyx to be worth a certain value that could be what the spell cares about and what you bought it for or what people in another area believe it to be worth could be completely irrelevant.

BTW that would be more akin to the water boiling example with perceived value in place of pressure.

That's a lot of ifs.

[Kyberwulf]

Okay this is how it works
The DM sets the for the Onyx gem at.. 20 gold

DM. you find a gem
PC what kind
DM make an Appraise Check
PC Rolls some dice.... and tells the DM
DM then notes he failed his Check
DM. You don't know what kind.
PC okay... i will put it in my bag.


PC reaches a town
PC. i sell my gem at the nearest place, then rolls a Gather Information Check.
DM checks somes notes.. Rolls an Appraise check
DM alright, you find an old man that is willing to buy your gem, he wants to buy it for... 30 gold.
The PC decides he wants 150 gold for the gem, tries to get the old man to pony up. rolls some diplomacy.... the old man doesn't go for it, his appraise told him it wasn't worth that much.

The PC walks away. After some failed attempts at trying to sell the gem at 150. He then comes back to the old man....
PC hey old man, i will sell this to you for 30
Old man says he doesn't want to buy it for 30 and drops his price to 15 they reach a price 20 gp. The PC leaves town feeling cheated.

Later in the week, the Old man is Approached by a Guy in a dark cloak, and has a chilly voice.
Mysterious Stranger. I hear you got gems for sale.
Old man Sure i do Sonny, wich you looking for
MS I am looking for a Gem, Black... Onyx to be exact.
OM Yer in luck! i got one in this week, Mighty Fine piece to i r'ekon
MS How much you asking for it?
OM 35 pieces
MS reaches into his pocket and Gives it to the Old man.
OM nice doin' buisness wit you!
MS walks away

Later that night .. the Myserious Stranger tries to Cast a spell, it fails

Does any one Know WHY the spell failed? And yes he was a Cleric trying to cast Animate Dead

[Thurbane]

You know, this sounds like like a niche for a new type of Inevitable: The Inevitable of Weights, Measures & Commerce. :smallbiggrin:

[Epsilon Rose]

That's a lot of ifs.
Just one: If the rules of magic are as stated. That's not a bad if. It's the same as saying you are cheating IF the rules say can only move rooks diagonally (that is purposely wrong) and you move yours in an L.

Okay this is how it works
The DM sets the for the Onyx gem at.. 20 gold

DM. you find a gem
PC what kind
DM make an Appraise Check
PC Rolls some dice.... and tells the DM
DM then notes he failed his Check
DM. You don't know what kind.
PC okay... i will put it in my bag.


PC reaches a town
PC. i sell my gem at the nearest place, then rolls a Gather Information Check.
DM checks somes notes.. Rolls an Appraise check
DM alright, you find an old man that is willing to buy your gem, he wants to buy it for... 30 gold.
The PC decides he wants 150 gold for the gem, tries to get the old man to pony up. rolls some diplomacy.... the old man doesn't go for it, his appraise told him it wasn't worth that much.

The PC walks away. After some failed attempts at trying to sell the gem at 150. He then comes back to the old man....
PC hey old man, i will sell this to you for 30
Old man says he doesn't want to buy it for 30 and drops his price to 15 they reach a price 20 gp. The PC leaves town feeling cheated.

Later in the week, the Old man is Approached by a Guy in a dark cloak, and has a chilly voice.
Mysterious Stranger. I hear you got gems for sale.
Old man Sure i do Sonny, wich you looking for
MS I am looking for a Gem, Black... Onyx to be exact.
OM Yer in luck! i got one in this week, Mighty Fine piece to i r'ekon
MS How much you asking for it?
OM 35 pieces
MS reaches into his pocket and Gives it to the Old man.
OM nice doin' buisness wit you!
MS walks away

Later that night .. the Myserious Stranger tries to Cast a spell, it fails

Does any one Know WHY the spell failed? And yes he was a Cleric trying to cast Animate Dead

Depending on the rules of magic? Not enough Onyx.
But that's a more scientific set of rules, like what you would find in FMA, where what you're really after is X amount of onyx.
If you're using magic like that in XXXholic where what you sacrifice is the important part it should work fine. In this system weather you're shrewd and get a discount or a fool and get charged extra is irrelevant, it's what you give up (the ability to buy something else with the gp) that is.

Both systems make sense for DnD, the first allows for the use of gems you find (though it could be argued that risking you're life and spending time was enough of a sacrifice under the second system) and make sense from a scientific standpoint. The second does a better job of balancing things and makes some sense from a magic stand point (everything has a cost and the universe doesn't care so much about the physical details); this system also provides a convenient explanation for why crafting costs xp and gp (you're sacrificing power and personal wealth to magic in order to bind an effect).

[only1doug]

Thank you for Proving my point further.
The point is, its still water,.. its still boiling... Your just trying to argue the that moving it around..changes it somehow


If you boil your water at Different Altitudes (http://en.wikipedia.org/wiki/High_altitude_cooking#Boiling_point_of_pure_water_ at_elevated_altitudes) then the temperature at which it boils changes, moving it around does change it.

[2xMachina]

My conclusion? Your training actually makes you think you need material costs.

As people with different training require different things, it means that NONE of the requirement is real.

Wheel of Time appears to use this system. The White Tower trainees require Somatic component to casts Fireball. The Aiel does not.

[Feytalist]

My conclusion? Your training actually makes you think you need material costs.

As people with different training require different things, it means that NONE of the requirement is real.

Wheel of Time appears to use this system. The White Tower trainees require Somatic component to casts Fireball. The Aiel does not.

Wheel of Time uses a different "spell" system than D&D, essentially making it similar to the mana pool (or "endurance pool" in this case) in most MMORPGs. There is actually WoT D20 RPG, with game mechanics on how its spells work.

There is some truth to what you say: spells like rainbow pattern (i think) has different descriptors for bards and for wizards (bards have to keep playing their instrument to keep the enemies fascinated).

My personal thoughts though, is that the actual size/volume of the material component matters most, not its cost, which is a variable concept anyway. Rewrite the PH inscriptions as "a single black onyx with a base value of 25gp". Everyone wins.