Legend

The legend of the origin of black onyx says that the Goddess Venus was resting on the banks of the the Indus River. As she slept, Cupid used the point of one of his enchanted arrows to give her a manicure. The parings of her nails then fell into the waters of the sacred river. Since the nails were of heavenly origin, they sank to the river bottom and were metamorphosed into black onyx.

Gemstone

Black onyx has a smooth, fine texture and is always black in color. Black onyx is a microcrystalline form of chalcedony quartz, The mircocrystalline structure is not visible to the naked eye so the stone appears to be dense and deeply colored. Most black onyx that is commercially available today is color enhanced (heat treated or dyed) to increase its depth of color. Some forms of onyx have bands or ribbons of white or tan against a black or brown background, these varieties are known as Sardonyx.

Originally, almost all colors of chalcedony, from white to dark brown and black were called onyx. Today when we think of onyx we often preface with the word "black" to distinguish it from other varieties of onyx that come in white, reddish brown, brown and banded sardonyx.

Black onyx is a medium hard stone that falls at 6.5 on the Mohs Scale of Hardness. Because of the this mid range degree of hardness all onyx material is good for cutting into beads and for carving. Black onyx is primarily mined in the Americas in Brazil, Uraguay and California and in India.

History and Lore

Black onyx is a semi-precious birthstone for Leos and the anniversary gemstone for the 7th year and the 10th year of marraige. Indians and Persians believed that wearing black onyx protected them from the evil eye, and that placing any onyx on the stomach of a pregnant woman in labor would reduce the labor pains and bring on an earlier delivery. Black onyx is still used today as a worry stone in the Middle East.

Black onyx is a protective stone worn when facing adversaries in battles or conflicts of all kinds, or while hurrying down a dark street late at night. In classical ceremonial magic, the image of the head of the God Mars or a figure of the hero Hercules was engraved on black onyx and carried for courage. Black onyx is not only used for protection, but also for defense against negativity conciously directed towards you.

Sources:
www.jewelsforme.com/Onyx-History.htm
www.jewellery-art.co.uk/black-onyx-meanings.html
www.wikipedia.com

Quartz Family Chalcedony Family Agate Bloodstone Carnelian Chalcedony Chrysoprase Fire Agate Jasper Onyx / Sard / Sardonyx