How much material silver is required to silver a greataxe, if the time and expertise is being provided as a favour?

Question

Suppose I own a greataxe, and a blacksmith owes me a favour. The Smith knows how to craft silvered weapons, and has agreed to do the work as a favour if I provide the raw silver.

The rules on silvered weapons state:

You can silver a single weapon or ten pieces of ammunition for 100 gp. This cost represents not only the price of the silver, but the time and expertise needed to add silver to the weapon without making it less effective.

So clearly the material silver is not worth 100 gp.

How much raw silver do I need to provide to the Smith as material?

My instinct is that the smith will primarily be working the silver into the cutting blades, so a few dozen silver coins would be sufficient. Thus a couple of gp worth of silver?

Is there any further RAW guidance about this? Are there standard interpretations/conventions to cover this?

Answer 1

The standard rule for crafting items is a 50/50 split between materials and labor

Both the PHB and Xanathar's Guide to Everything present rules for crafting items as a downtime activity. While the rules differ in some respects, they are consistent on the most relevant bit: the cost of crafting an item is split evenly between the cost of materials and the cost of labor. From the PHB section on Crafting (as well as the corresponding section in the Basic Rules (emphasis added):

You can craft nonmagical objects, including adventuring equipment and works of art. [...] You might also need access to special materials or locations necessary to create it. [...]

For every day of downtime you spend crafting, you can craft one or more items with a total market value not exceeding 5 gp, and you must expend raw materials worth half the total market value.

And the crafting rules in XGtE agree:

A character who has the time, the money, and the needed tools can use downtime to craft armor, weapons, clothing, or other kinds of nonmagical gear. [...] In addition to the appropriate tools for the item to be crafted, a character needs raw materials worth half of the item’s selling cost.

Regardless of which crafting rules you use, you need half an item's value in raw materials in order to craft that item.

What about silvering an existing item?

Strictly speaking, silvering an item is not the same as crafting a new item, so the above rules do not apply directly to this case. However, I am not aware of any rules specifically for silvering weapons that would answer this question, which means the DM is empowered to make a ruling. In my opinion, a DM looking for guidance in making such a ruling would be entirely justified in using the above rules as a precedent to say that silvering a greataxe requires 50 gp worth of silver (and perhaps other materials) and 50 gp worth of labor.

How much silver is that anyway?

50 gp worth of silver would be 500 silver pieces. By the rules, 50 coins of any type weigh 1 pound, so this would represent 10 pounds of silver. At 10.49 g/cm³, that makes about 430 cubic centimeters of silver, or just under half the volume of a 1-liter bottle. (I've elided the tedious unit conversions. You're welcome.)

However, the actual amount of silver might be less than this, since it's possible that other materials are also required for the silvering process, and the costs of these materials would also be part of the total material cost of 50 gp.

As to whether this is anywhere in the ballpark of the quantity of silver that would be required to silver a greataxe in real life, I have no idea.

Answer 2

An incidental, token amount

In-Game Reasoning

The rules of silvering you present are correct, but they also mean that it costs the same to have any weapon (or ten pieces of ammunition) silvered. It will still cost 100gp, whether you need the amount of silver required for ten blowgun darts, a dagger, or a greatsword.

Since the cost of the process is the same regardless of how much material is involved, it stands to reason that the value of the "time and expertise" is considerably more than that of the silver itself. Perhaps the smith, by charging the same regardless, is making a little less profit on a greatsword than a dagger, but apparently the difference is not enough to warrant a variable rate.

Furthermore, adding this silver (a relatively soft metal, at least compared to iron or steel) to the weapon is neither reducing the weapon's effectiveness (as stated in the rules) nor increasing its weight (assumed since it does not state that the properties of the weapons change, and increased weight would certainly affect the range of ammunition).

Thus we can conclude that the actual amount of the silver is negligible compared to the "time and expertise" needed to successfully work it, and is certainly less than the initial weight of ten blowgun needles.

Meta-game Reasoning

Comments on this answer suggest that the DM is trying to break up the standard 100gp price of silvering. It may be worth considering why.

Is it that the DM is rewarding you for role-play with the blacksmith owing you a favor? In this case the DM should decide how much of a discount on this standard service they would like you to get, and that decision should be based on how much they want to reward you, not on an accurate calculation of silver content.

Is it that the DM is willing to reduce the price for a desired service in return for a 'fetch quest' of you bringing silver to the smith? This is trope that can be usefully employed, although silver seems an odd choice as it is abundant in most game worlds. In any event, the answer to how much silver you would need becomes 'as much as I acquired in the quest set up by the DM', and again accuracy of calculation is not important.

Is it that the DM is trying to build an internally consistent economic system in the game, which can allow material values to interact with labor costs? Good on them! But I would suggest that they start with high consequence, frequently occurring interactions. If your game is not one in which you frequently are owed favors by skilled craftspeople resulting in such deals, accurate calculation of this particular exchange is unlikely to be useful in setting up the system.

Conclusion

If the blacksmith owes you a favor, but you have to supply the silver, any small, token amount of silver should do. Give the smith a handful of silver coins or a small silver item. This will fulfill any role-playing aspect of you providing the smith with silver without having to accurately calculate what is a negligible and ultimately meaningless price.