Minerals described in 1878

Krennerite is an orthorhombic gold telluride mineral which can contain variable amounts of silver in the structure. The formula is AuTe2, but specimen with gold substituted by up to 24% with silver have been found ([Au0.77Ag0.24]Te2). Both of the chemically similar gold-silver tellurides, calaverite and sylvanite, are in the monoclinic crystal system, whereas krennerite is orthorhombic.

Tincalconite is a hydrous sodium borate mineral closely related to borax, and is a secondary mineral that forms as a dehydration product of borax. Its formula is Na2B4O7·5H2O or Na2[B4O5(OH)4]·3H2O.

Tarapacáite is the mineral form of potassium chromate with the chemical formula K2CrO4. It forms bright yellow crystals and was discovered in 1878. It is named for the former Tarapacá Province, Peru; nowadays belonging to Chile. The boundaries between Peru, Bolivia and Chile were vague in the Atacama Desert before the War of the Pacific (1879–1883). Its type locality is Oficina Maria Elena, Maria Elena, Tocopilla Province, Antofagasta Region, Chile. It is unlikely to occur anywhere except in highly arid conditions as it is easily soluble in water.