The alloy of White Mithril and small quanities of Adamantium forms a substance known as Black Mithril.

Created almost exclusively by dwarves, this substance is slightly sturdier and weighs slightly less than White Mithril. Most importantly, it can hold a higher level of enchantment than White Mithril, without needing large quantities of Adamantium. For this reason, wizards frequently seek out small quantities of Black Mithril for small magic items such as rings, amulets, and sometimes even wands.