Orthorhombic crystals, multifaceted and often striated primes with perfect and transparent cleavage.

The zoists, named after the Austrian mineralogist Von Zois, were discovered in 1805 in the Carinthian Alps, hence the original name of saoualpite.

In recent decades, significant deposits of gem qualities have been exploited; previously only a few gem samples of various colours existed: colourless, green, brown.