How to clean it
Warm soapy water and a soft cloth.
Black, or black banded with white
Onyx
The birthstone for February.
Properties
Composition
Banded chalcedony
Hardness (Mohs)
6.5–7
Crystal system
Trigonal
Colour
Black, or black banded with white
Mined in
Brazil, India, Madagascar, USA
Worth knowing
Most solid black onyx is dyed grey chalcedony. Naturally uniform black onyx is scarce.
History
The Greek onyx meant fingernail — the pale banding reminded them of it.
Practical
Caring for Onyx
How to tell it is real
Nearly all solid black onyx is dyed grey chalcedony — industry norm, not a scam. Naturally uniform black onyx is genuinely scarce.
One general rule covers most mistakes: never store stones loose together. Diamond at 10 on the Mohs scale scratches everything else you own, and it does not need much contact to do it.
What that hardness means in practice
Softer than household dust. Better in earrings or a pendant than in a ring, where it takes constant knocks.
Traditional associations
Onyx is traditionally linked to discipline, endurance and holding a boundary. In chakra systems it is placed at the Root, and in elemental correspondence it is assigned to Earth.
These are cultural associations recorded across various traditions, not claims about physical effects. The composition and hardness above are measurable; this paragraph is folklore, and worth reading as such.
Questions
What is Onyx made of?
Banded chalcedony, crystallising in the trigonal system.
Which month is Onyx the birthstone for?
February.
Where does Onyx come from?
Brazil, India, Madagascar, USA.
How do I clean Onyx?
Warm soapy water and a soft cloth.
How can I tell if Onyx is real?
Nearly all solid black onyx is dyed grey chalcedony — industry norm, not a scam. Naturally uniform black onyx is genuinely scarce.
Can I wear it every day?
At 6.5–7 on the Mohs scale, not in a ring. Keep it to pieces that take fewer knocks.