Description
Black Onyx is a rich, opaque jet black stone known for its simple but elegant beauty.
The name comes from the Greek word onux which means 'fingernail', and
originally referred to the pale colours of some varieties of Onyx as well as the darker
colours. Since ancient times, Black Onyx has often been heated to enhance its richness of
colour. Similarly, clean grey agate has been treated since ancient times to turn it black,
and today treated agate is often sold as Black Onyx.
The Science
Black Onyx is a variety of chalcedony which is a microcrystalline quartz.
6.5 - 7 on the Moh's Hardness Scale
Care and Cleaning
Soft polishing cloth, plain water rinse or mild solution of soap and water. Black onyx
may chip or scratch rather easily, so should be stored separately from other jewellery.
History
The Romans first popularised the use of Black Onyx, and their story of its origin tells
of how Cupid cut the fingernails of the goddess Venus with an arrowhead while she was
sleeping. He left the clippings scattered on the sand, where they were changed to stone by
The Fates so that no part of the divine body would ever decay.