Red Onyx is a treated chalcedony! Chalcedony is a member of the extensive quartz family and has a density of 6-7 on the Mohs scale. Red Onyx is known for its semi-transparent orange-red colour.
Red Onyx is easily confused with "real" carnelian and is, sadly, often sold under that name. Namely, as carnelian is sometimes referred to as red onyx for convenience. Treated chalcedony is often totally even in colour. In contrast, carnelian is often striped and has more colour differences and structure to it. This is very noticeable when held against the light.
Amongst others, chalcedony can be found in Brazil, Madagascar, Uruguay, India, the United States, Great Britain, and Namibia.
Chalcedony is related to the zodiac signs Cancer, Sagittarius and Gemini. Read more on which gemstones match which zodiac signs on this page!