Gemstone Spotlight: Black Spinel vs. Black Onyx, What's the Difference?

We use black as a bold gemstone in many of our KIR pieces but depending on the application it will be a black onyx or black spinel bead and we thought you might be curious about the difference and why we choose to use one over the other or don't just use one variety across the board. Most of the time black onyx is used for more of a center focal stone in a larger piece and black spinel is used for beading on a smaller scale. 
Black Onyx is a banded variety of the oxide mineral called chalcedony. Therefore, it is made up of alternating parallel bands of color (which is hard to see in black but it is there!) composed of quartz and moganite. Onyx can be sourced from many places around the world and has been used in artwork for centuries among many geographic areas. It has been utilized in anything from buildings to sculptures and, of course, hand-carved jewelry.
Spinel is a vitreous aluminum oxide gemstone that can commonly be mistaken for sapphire or ruby because of its similarities in beauty and sparkle especially since it comes in a wide range of colors of reds, purples, blues, oranges, yellows, browns, and blacks. The black spinel has been seen as incredibly elegant as it has been mined for centuries and even acquired the nickname as "the black prince's ruby" as it was featured as a main focal point in England's state crown. Spinel is popular in jewelry making because it does come in such a variety of colors and sizes and is easily set in many ways. 
Both are highly durable stones which makes them great options for any jewelry piece and black gems will always be incredibly striking. All in all, black onyx's more hard, mineral, opaque properties make it viable for larger stone and bead features and also give it less sparkle than the black spinel that is so similar to other gemstones and can be cut and molded into smaller shapes for more small, delicate beading designs. 
KIR Collection Riana Lariat in Black Onyx


  • An informative article about black Onyx vs Back Spinel. I would like to add one more thing regarding black spinel – A black spinel is a type of spinel that has a deep black color. Black spinels are rare and are in demand by people who collect gemstones.

    Amida Lui
    chief writer for

    Amida Lui
  • Thank you the article is very informative

    Bibo Saba

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