19 Photos
Zincite
Chemical Formula	(Zn,Mn)O
Species	Oxides & Hydroxides
Crystal System	Hexagonal
Mohs Scale	4
Specific Gravity	5.64-5.68
Color	Yellow-orange to deep red, rarely yellow, green, colorless
Streak	Yellowish orange
Luster	Sub-Adamantine
Refractive Index	n = 2.013 n = 2.029
Diaphaneity	Transparent, Translucent, Opaque
Cleavage	Perfect perfect, but difficult.
Fracture	Conchoidal
Crystal Habit：Disseminated – occurs in small, distinct particles dispersed in matrix.

Zincite is the mineral form of zinc oxide (ZnO). Its crystal form is rare in nature; a notable exception to this is at the Franklin and Sterling Hill Mines in New Jersey, an area also famed for its many fluorescent minerals. It has a hexagonal crystal structure and a color that depends on the presence of impurities. The zincite found at Franklin Furnace is red-colored (mostly due to iron and manganese) and associated with willemite and franklinite.

Zincite crystals can be grown artificially, and synthetic zincite crystals are available as a by-product of zinc smelting. Synthetic crystals can be colorless or can range in color from dark red, orange, or yellow to light green.

Both natural and synthetic zincite crystals are significant for their early use as semiconductor crystal detectors in the early development of crystal radios before the advent of vacuum tubes. As an early radio detector it was used in conjunction with another mineral, chalcopyrite, and this combination was known as the cat's-whisker detector.