All moonsilver was created by Luna, condensed out of pure Wyld to form a brilliant silvery metal that takes on an iridescent sheen in moonlight. Most of Creation's original deposits of moonsilver have been consumed in the Second Age, but Luna continues to create more at the edges of the Wyld, where the Lunar Exalted dwell. It must be harvested by moonlight, without the aid of tools, and purified in a sacred forge with the aid of a No-Moon sorcerer.
Moonsilver shares the protean nature of Luna, and moonsilver artifacts can change shape along with their wearer. It is used in the moonsilver tattoos that allow modern Lunars to fix their caste and resist the chimeric mutations of the Wyld. Lunars are extremely possessive of this metal; even other Lunars must earn the right to carry moonsilver artifacts, and anyone other than a Steward using it is an insult.
Due do its shape-changing qualities, moonsilver armor has no mobility penalty. Moonsilver weapons, when properly attuned, are supernaturally accurate; ranged weapons also travel further than would normally be possible.