I was looking to create some mithral armor (breastplate) in a game that I have recently reached 3rd level fighter in.
In the DMG, it states that when creating a magical item, the material the item is made of would be required (+ 500gp, know-how and time), in this case mithral.
The mithral armor itself allows both the breastplate and chain shirt variants to be worn under clothes and the variants (e.g. plate) that normally impose a stealth disadvantage to forgo that disadvantage.
It may be that mithral is extremely rare or as common as quartz in the world, however based on the effect of mithral armor and from a purely game balancing perspective what would be a fair price for merchants to charge for the material mithral in weight?
Breastplate = 20 lbs
Plate = 65 lbs