The two main items made of mithril are the dwarvish and elven mithril-coats. The Amulet of Yendor is also made of mithril, though this does not have any noticeable effect on its properties, other than the fact that this prevents it from being damaged.
_Mithril_! All folk desired it. It could be beaten like copper, and polished like glass; and the Dwarves could make of it a metal, light and yet harder than tempered steel. Its beauty was like to that of common silver, but the beauty of _mithril_ did not tarnish or grow dim. [ The Fellowship of the Ring, by J.R.R. Tolkien ]