The Gems of GemStone
Onyx Back Next

Color range: brown, white, grey, and black

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Onyx is the striped, semiprecious variety of agate with white and black alternating bands. Other varieties include carnelian onyx, with white and red bands, and sardonyx, with white and brown bands. Its properties are the same as those of quartz. Onyx is used in carved cameos and intaglios because its layers can be cut to show a color contrast between the design and the background.

The name onyx comes from the Greek word "onux", which means fingernail.   The story is that one day Cupid cut the divine fingernails of Venus with an arrowhead while she was sleeping.   He left the clippings scattered on the sand and the fates turned them into stone so that no part of the heavenly body would ever perish.   Black isn't normally the color one associates with fingernails.   But for the Greek almost all colors of chalcedony, from fingernail white to dark brown and black, were called onyx.   Later, the Romans narrowed the term to refer to the black and dark brown colors of chalcedony only.  

For hundreds of years, it was carved to produce cameos as the contrast between the different colored layers heightened the relief.  Since ancient times, onyx has been dyed to improve it's color.  Often treated agate is sold as black onyx.

It has been used to alleviate grief, promote self control and wise decision making and to bring happiness and good fortune. This stone promotes increased vigor, strength, stamina, constancy, steadfastness, permanence, tenacity, firmness and durability.  Valuable in difficult or confusing times of our lives.  It is considered to be useful in the treatment of heart trouble, ear/hearing problems, watery eyes, hair problems and disorders related to bone marrow.  It is thought to relieve stress by enhancing self control and inspiring serenity.

Onyx is the anniversary gemstone for the 7th year of marriage.  Black onyx is the anniversary gemstone for the 10th year of marriage.  It is the zodiac stone for Leo (23 July to 22 August.)