Hello fellow Playgrounders! My question is a bit long, so if you're in a hurry skip to the Short version. I anticipate here that what I need help for is to determine the correct "numbers" and "amounts" of what I'm going to explain.

Here's the Long version, spoilered for convenience to avoid Wall of Texts.

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For my forthcoming campaign, I wanted to tweak a bit the magic item creation process: my players never liked the loss of XP associated to the creation, so they never pick creation feats and only resort to buying MI, or finding them. While I try to give them interesting and useful items, sometimes occurred the unpleasant situation where one of my players didn't like what I gave him; moreover, while the players gain levels, it is sometimes hard to justify the reason behind the presence of a high level magic item in an area where lower level creatures dwell.
In my brief experience with 4th Edition, I liked the idea behind that magic dust that could be extracted by pre-existing magic item, destroying them in the process: so I tried to recreate such a mechanic, adapting it to my campaign.
What I had in mind is basically this.

Magic items can be destroyed and a magic dust containing portions of its power can be extracted from it (a process that in the following will be referred to as "dustifying"); every item can be dustified apart from Potions, Scrolls and Wands: to dustify an item a character must perform a magic ritual lasting 1 day, requiring a Spellcraft check (DC 10 + item CL). Magic wielders automatically know how to perform such a ritual, whereas non casters must pick the following feat:

Crafting Affinity
The character understands the intrinsic nature of magic item and knows how to make and unmake their substance.
A non caster character picking this feat can perform the dustifying ritual to extract the magical dust from an item; he gains a +2 bonus to his check.
Plus, even if unable to cast spells, this feats enables his to pick Item creation feats: he is treated as a Primary caster with an effective caster level for the prerequisites equal to his current level minus 2; the same effective caster level applies to the prerequisites needed to craft items (such as minimum CL).
The nature and amount of the extracted dust depends on the item dustified: it has different colour and consistence depending on the school to it associated:
  • Abjuration: very heavy grain dust, violet;
  • Enchantment: light grain dust, golden and shiny;
  • Divination: very light grain dust, very light blue (almost white);
  • Conjuration: very heavy grain dust, dark blue;
  • Evocation: mixed grain dust, flame red;
  • Illusion: very light grain dust, sky blue;
  • Necromancy: mixed grain dust, dark gray (almost black);
  • Transmutation: mixed grain dust, emerald green;
  • Universal: mixed grain dust, light gray.

Whatever the school, the dust weights 1lb for each 100gp of its value.
A dustified magic item provides dust of the corresponding to the associated aura; in case of multiple auras, the dust is of the strongest school, and in case of equal strength, the amount of dust is equally divided between both schools.
The extracted dust can be used, during the creation of another magic item, to replace the following:
  1. the money needed to craft the item itself, up to half of the crafting cost;
  2. the XP associated to the crafting, keeping in mind the equation 1 XP = 5 gp;
  3. the prerequisite spells needed to craft the new item.

The dust needed for points a) and b) doesn't have to be from any particular school; on the other hand, point c) requires that for each spell the dust replaces, one has to provide dust of the correct school: for example, a character wishing to replace the Glitterdust spell must provide Conjuration dust.

Now let's come to the real question, which is twofold. In a first draft of such a system, I decided that by dustifying an item one extracts an amount of dust equal to 5% of said item market value: that is, dustifying a Medallion of Thoughts (market price 12000gp), one gets 600gp in Divination dust (incidentally weighting 6lbs).
While replacing spells in item creation, I decided that for each spell to replace one has to provide dust amounting to 500gp x spell level x minimum caster level to cast the spell: for spells featuring in multiple spell lists, one picks the combination spell level/minimum caster level that gives the lowest product.
Are these numbers good enough for my purpose? Do they impact too much on the economy of the game, or they break it? Are they too cheap, too expensive or balanced enough?

Example: an 8th level Fighter with the Crafting Affinity and Craft Magic Arms and Armors feats wants to forge a new weapon. For the purpose of the power of the item, he has an effective caster level of 6th (which, incidentally is enough to pick Craft MAaA), meaning that he can create a weapon with a maximum bonus of +2. He chooses to craft a +1 Thundering Battleaxe: the Thundering special ability has a Price of "+1 bonus", a CL of 5th and requires the spell Blindness/Deafness.
Blindness/Deafness is a Sor/Wiz 2, Clr 3 and Brd 2 spell, and the lowest spell level/caster level combo is Wiz 2, since a 3rd level Wizard can cast 2nd level spell. The Fighter must therefore provide 500 x 3 x 2 = 3000gp in Necromancy dust. Note that to obtain such an amount of dust, he has to dustify Necromantic items for a total cost of 60000gp.
At the moment, the market price for the battleaxe is 310 (MW battleaxe) + 8000 (+2 bonus) = 8310gp, for a creation cost of 4155gp + 333XP + 3000gp in NecroDust.
Not wishing to expend XPs, he chooses to provide additional dust of a random school, for a total amount of 333 x 5 = 1665gp; the grand cost at the moment is 4155gp + 3000gp in NecroDust + 1665gp in RanDust.
Wishing to achieve the minimal expenditure of gps, the Fighter provides half of the creation cost in Random Dust, for a final price of 2077.5gp + + 3000gp in NecroDust + 3742.5 in RanDust.

Do you think these numbers make sense or are utter crap? Note, I'm not questioning the soundness of the system, only the numbers. What do you think?


Here's the Short version.

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I want to change the item creation process: one can perform a ritual on magic items to destroy them and extracting a magic dust, of the school associated to the aura of the destroyed item, which he can use to replace:
  1. the money needed to craft the item itself, up to half of the crafting cost;
  2. the XP associated to the crafting, keeping in mind the equation 1 XP = 5 gp;
  3. the prerequisite spells needed to craft the new item.

The dust needed for points a) and b) doesn't have to be from any particular school; on the other hand, point c) requires that for each spell the dust replaces, one has to provide dust of the correct school.

In a first draft of such a system, I decided that by destroying an item one extracts an amount of dust equal to 5% of said item market value.
While replacing spells in item creation, I decided that for each spell to replace one has to provide dust amounting to 500gp x spell level x minimum caster level to cast the spell: for spells featuring in multiple spell lists, one picks the combination spell level/minimum caster level that gives the lowest product.

Are these numbers good enough for my purpose? Do they impact too much on the economy of the game, or they break it? Are they too cheap, too expensive or balanced enough?