Learning Library

Onyx Gemstone

A member of the Agate group of Chalcedony’s,  which in turn is a sub species/family of Quartz, Onyx is viewed by many as a jet black, highly fashionable gemstone.

In its naturaly state, Onyx, meaning  ‘veined  gem’, differs from other Agates in that its  lines  of  colour  banding  (normally  black  and white) are straighter. When Onyx is pure black it is referred to as “Black Onyx” and owes its distinctive colour to an ancient dyeing process.

In its natural form, this gemstone is available  in  a  variety  of  colours:  white  and  red  bands  (Carnelian Onyx), and white and brown bands  (Sardonyx). 

Roman soldiers wore  Sardonyx as talismans,  believing that it made the wearer as brave as the  heroes they had engraved onto the gem. Onyx is  said to eliminate negative thinking and sharpen  the wits, instinct, intuition and helps to change  one’s habits.

Because of its different colour bands, the gem  is ideal for making cameos, where the lighter colour  tends  to  be  carved,  using  the  darker  colour as the background. It is a well-known  member of the Chalcedony group of gems, who  in turn belong to the Cryptocrystalline family  of Quartz. Some also refer to the gem as “Black  Magic”.

Over  the  past  decade  the  world’s  leading  jewellery designers, such as Cartier, Chopard  and  Gucci,  have  all  incorporated  Onyx  into  many  of  their  jewellery  and  watch  designs.    Sarah Bennett also uses the gemstone to great  effect in many of her bold gemstone designs.  Sarah believes that the gem’s true jet blackness  provides it with one of the best eye catching  lustres in the gem world. I have to agree (well  of course I do because she is my wife), that  because Onyx is 100% opaque, it does have  one of the best lustres in the gem world, a lustre  that in my opinion is only bettered by Swiss Marcasite.

Back to Learning Library

A big and bold Black Onyx Sarah Bennett cocktail ring.