The Magic Circle spell requires powdered silver and iron worth at least 100 gp to cast it; how much powder is that?

Question

The component for casting Magic Circle is 100 gold pieces worth of Powdered Silver and Iron (or Holy Water, which we are not discussing here). 100 gold pieces is equivalent to 1000 silver pieces. At an average weight of one pound for 50 coins, that is 20 pounds of silver. Iron weighs less than silver (about 12% lighter) but is also worth much less, so adding more iron would probably only increase the weight.

How do you handle this in your game? Do you make your wizards carry 20 pounds of powder to cast Magic Circle one time? Is there an official interpretation of this component somewhere? What solutions have other DMs come up with?

The only idea I have come up with is that labor costs are high to powder any metal so that grinding a handful of silver costs 98 gold pieces - leaving about a half a pound of powder per casting.

Answer 1

Have you ever read the Mistborn books? Magic in those books is powered by metal, which means there's an active trade in the specific alloys they need, with skilled metallurgists getting quite wealthy for providing just the right sorts of metal to highborn magic-users.

Why do you need such skilled metallurgists? Well, everyone can get normal copper or iron or such. But for magical purposes, the metal needs to be extremely pure, with extremely specific amounts of each element, and in the right form factor too. If you use impure metals, at best the magic won't work, and at worst you'll die.

I would rule the same for the components of magic circle. 100gp can buy you 20 pounds of silver, sure, but that'll be normal silver. Good enough for making coins and silverware out of, but nowhere near good enough for magic. 100gp only buys a small pouch of silver in the right formulation for a magic circle.

Mechanically, the weight of spell components is assumed to be generally negligible, even if those components cost money. Their value comes from the specific materials used, not the quantity of it—there's a reason there's no spell whose material component is "a cubic meter of granite", even though that might add some interesting resource-tracking to the game! So it follows that there's something special about the components of magic circle that makes them worth 100gp without weighing 20 pounds.

Answer 2

I think the problem might be that you are looking at this too literally or mathematically. It's good to remember that D&D is a fantasy world. There are some things that loosely match the ideas of weight and physics, but not necessarily. Also, the 100g coins' worth of powdered silver and iron may not weigh much. The cost of asking a smith (presumably) to grind silver and iron into a fine and pure powder will be included in the price. So the smith could charge 100g pieces for this product even thought it may not weigh all that much. It also does not specify ratio: silver is likely to be more expensive than iron in most campaign settings so the powder may only contain a small amount of iron.

In my campaigns I have allowed this to be a negligible weight which the wizard can carry in a component pouch (PHB, p.151).

I do not always use encumbrance (PHB, p.176) in my campaigns, mainly because it's a monumental bore. But, I have in the past, when I had players over-stepping the mark and wanting to carry two elephants' worth of belongings with them as they adventured. They learnt that that's what a trusted pony or donkey is for!

The alternative, which is much lighter potentially is holy water. 4lbs would cost 100g. (PHB, p.151) But, it may be much more pricey in your campaign if you want it to be. A few droplets could cost a 100g!

Answer 3

As mentioned in the answer by Draconis, purified and powdered silver can indeed be quite more valuable than the silver that is good enough for minting coins.

Moreover, not only do you have a problem with purifying silver, but you have the problem of it becoming impure. Specifically, tarnish. Silver will react with airborne sulfur and when you powder it you greatly increase the contact area, thus speeding the reaction. Thus considerable care must be taken to keep your environment uncontaminated and then seal up the result into a packet for the caster.

And how are you powdering your silver? When you apply destructive force to an object you generally get a bit of material transfer from the source of the force application to the target. Note how any abrasive wears down over time--that's going into your product. Most abrasives are used remove material and that doesn't matter, but in this case we are keeping it. Somehow they need to purify it while retaining it's powdered nature.

(Personally, I figure a lot of this actually involves magic. We only see the combat-focused part of magic, but it seems very unlikely that there aren't other spells. Thus in cases like this you're not paying for a lot of labor, you're paying for some caster's time.)