Clinohumite, a magnesium silicate, is an uncommon member of the humite group. It is most commonly found as tiny indistinct grains. Large clinohumite crystals are sought by collectors and are also fashioned into bright, yellow-orange gemstones. Pamir Mountains (Tajikistan) and Taymyr (Northern Siberia) are the two sources of gem quality clinohumite.

Clinohumite – a monoclinic mineral – is typically a dark to light brownish or orange – yellow in color. It resembles the hessonite variety. Clinohumite is usually granular, but may also be prismatic. Crystals are almost always small.

Clinohumite is brittle and has a hareness of 6. Its fracture is uneven and conchoidal. Clinohumite may vary from transparent to translucent. Its luster varies from a dull vitreous to resinous.

Under shortwave ultraviolet light, some clinohumite may fluoresce orange – yellow but there is no fluorescence under long wave UV rays.