Is mined in Brazil, India, California and Uruguay however it is available worldwide and stained to enhance vibrant colour and is part of the quartz family. The name is derived from the Greek word “onyx” which means fingernail. Onyx is made of minerals like marble, granite however natural black gem is uncommon therefore agate is soaked in a sugar solution, then heating it in sulphuric acid to carbonise the sugar particles. Heat treatment is also given to enhance the colour and shine, all treatments must be declared by the supplier. Onyx is mostly free from inclusions.
The gem itself is black sometimes dark brown with white stripe across. The colour is dominant and used in beautiful rings, pendants and broaches it is deal for carving giving it a minimalist and contemporary look with a smooth wax-like appearance. Onyx is also used as beads in necklaces and bracelets and contrasts well with yellow gold for bold appearance and when set in silver gives it the art deco style.
Onyx symbolises birth stone for December and 7th wedding anniversary also said to promote stamina, alleviate worries and fears.
Onyx is a reasonably durable gemstone however it will need to be looked after to keep it looking beautiful. Onyx should be stored in a soft pouch or jewellery box to prevent scratching and damage. Soap and liquid cleaners should be avoided as these may cause the stone to become dull. Harsh detergents or chemicals such as bleach or chlorine could cause erosion of the stone. To clean onyx jewellery rinse thoroughly with water and dry with a soft jewellery cloth, it is not recommended for ultrasonic cleaners.