lengenbachite

from The Century Dictionary.

• noun A sulpharsenite of lead with antimony, silver, and copper in small amount; it occurs in thin-bladed crystals, probably triclinic, of steel-gray color and metallic luster: found in the dolomite of the Binnenthal, Switzerland.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun mineralogy A triclinic mineral containing arsenic, copper, lead, silver, and sulfur.