[8][12] These techniques are still used, as well as other dyeing treatments, and most so-called "black onyx" sold is artificially treated.

[8] Onyx can be found in various regions of the world, including Greece, Yemen, Uruguay, Argentina, Australia, Brazil, Canada, China, Czech Republic, Germany, Pakistan, India, Indonesia, Madagascar, Latin America, the UK, and various states in the US.

It has also been used for intaglio and hardstone cameo engraved gems, where the bands make the image contrast with the ground.

The German sculptor Ferdinand Preiss used Brazilian green onyx for the base on the majority of his chryselephantine sculptures.

[18] Green onyx was also used for trays and pin dishes – produced mainly in Austria – often with small bronze animals or figures attached.

[20] Sardonyx (onyx in which white layers alternate with sard - a brownish color) is mentioned in the Bible as well.

[22] The first-century naturalist Pliny the Elder described both types of onyx and various artificial treatment techniques in his Naturalis Historia.

[11] Slabs of onyx (from the Atlas Mountains) were famously used by Mies van der Rohe in Villa Tugendhat at Brno (completed 1930) to create a shimmering semi-translucent interior wall.

The ancient Romans entered battle carrying amulets of sardonyx engraved with Mars, the god of war.