Also called zinc blende, blende, blackjack, and mock lead, pure sphalerite is nearly colorless, but it is commonly brown, yellow, black, or dark red because of impurities. It has a white to dark-brown streak, always lighter than the color of the specimen. The mineral crystals are usually shaped like triangular pyramids, with three sides and a base. Because it has good cleavage in six directions, sphalerite will break into 12-sided blocks. It has a brilliant resinous or metallic luster, and it can be scratched by a knife.
Some sphalerite is found as massive deposits varying from coarse to fine grained.
The best specimens found in Kansas are from the lead and zinc mines of Cherokee County. Sphalerite from Cherokee County. Generally it is white or colorless, but it may be tinted gray, red, green, or blue. It can be scratched with a knife but not with a fingernail. Among the finest calcite crystals in Kansas are those from the lead and zinc mines of Cherokee County.