Gem of the Month: Black Spinel

sr-a012.jpgThis is the first in a series of articles brought to you by Aussie Sapphire – this month, the featured gem is Black Spinel, the premier black gemstone.  Black spinel (9.3 carat emerald cut)

Black spinel is not well-known among the gem world, yet its outstanding features make it the ideal choice for an opaque black gem. These days, where most gems undergo routine enhancement treatments, black spinel can stand proud as a gem requiring nothing more than cutting and polishing to bring out its inner beauty. If you want a totally natural and untreated black gemstone – black spinel is the one!

Gemmology matters: Spinel (MgAl2O4) is a mineral similar to corundum (Al2O3) and is often found in ruby and sapphire bearing areas. Spinel comes in a variety of colours but the relatively rare opaque black variety is only found in a few areas – traditionally Thailand is the main source but Australia is also a major producer. With a hardness of 8.0, uniform nature, high reflectance and lack of cleavage, black spinel makes excellent gem material. Black spinel has been often called “black sapphire” or “nin” in Thailand. Miners here often call it Blackjack and regard it as an indicator of good sapphire being present in the wash. Let there be no confusion though as black spinel is an excellent gemstone in its own right.

Mythology and Lore: There is a wealth of mythology surrounding black spinel. It is believed to protect its owner from harm, to reconcile differences, and to console sadness. Some say that black spinel is the stone for people born on Saturday and it is the recommended gift for the 22nd wedding anniversary.  While in Western culture, black may be associated with evil or mourning; in other cultures, black may represent power, fertility or wisdom (source Wikipedia). In any case, black is the essence of style and sophistication with a timeless quality that means it will never go out of fashion.

Black Spinel Cab Earrings in SilverAlternatives in black: There are a number of alternative products to black spinel – all with a number of disadvantages.

(photo at left shows silver earrings with 6 carat cabbed black spinel).

Black Diamonds have become extremely popular in recent years with a price tag to match. Although diamond is the hardest material at 10 on the Mohs scale, the high level of dark coloured inclusions in black diamond weaken the stone making it difficult to cut and polish. Almost all commercially available gems have been heated and irradiated to produce a dark colour and larger gems are difficult to find.

Black Onyx is widely available but inferior for use in jewellery. With a hardness of only 6.5-7.0, onyx is susceptible to damage. Buyers must assume that all commercially available black onyx has been heated and dyed to achieve the black colour as naturally occurring onyx ranges from white to brown, often with striping. Black onyx is the easy option but it is not the best.

Jet was made popular by Queen Victoria who wore it as mourning jewellery after the death of Prince Albert.  Jet is really a form of highly compressed coal and is extremely soft (3.0-4.0 Moh) so should be worn with great care to avoid damage.

For those interested in how black gemstones might be used to make a striking fashion statement, here are a few links of interest:

The Rainbow Collection – black spinel/pearl necklace
Black Spinel choker from Novica
Bernadine Fine Art Jewelry – black gems

Of course, here at Aussie Sapphire, we have a range of exclusive jewellery featuring black spinel and loose gems which may be used in a jewellery setting of your choice. See our online shop to browse our selection of Black Cat Jewellery and Black Spinel gems.

We hope you found this article of interest – we welcome your comments so feel free to contribute. Stay tuned for the next article which we will probably do on aquamarine.
cheers from Aussie Sapphire


10 Responses to Gem of the Month: Black Spinel

  1. Just listed some black spinel beads on the Aussie Sapphire main website – see under the Jewellery section of the online shop (select beads). Getting lots of orders for loose gems also – are in the process of cutting some more now to keep up with demand.

    cheers from Aussie Sapphire

  2. We now have a large stock of cut black spinel in our online shop – all shapes and sizes.
    Please see this link for the Black Spinel catalogue:

    cheers from Aussie Sapphire

  3. […] For those of you who have not yet discovered this great gem – see our previous “Gem of the Month” on Black Spinel – the premier black gemstone. […]

  4. bill says:

    i have found a stone black and hard.near quartzite bedrock flagstone,some jasper and can i identify it ?

  5. GemSelect says:

    The black spinel look stunning, though we never seem to see it here in Thailand.

    How about black tourmaline as an alternative? Not as expensive as as black diamond and certainly more durable than onyx. We’ve found the black tourmaline rough at good prices and have cut some impressively large pieces (some over 50 cts).

  6. bob says:

    Does Black Spinel when put under light glow a red color? when i do mine it looks like it is red in the deep gem…

  7. mike says:

    hi while i was over seas in asia i found i black stone its about the size of a small tenni s ball very shiny and hard near perfectly round any information would help thanks

  8. Creme Swirl says:

    Creme Swirl…

    […]Gem of the Month: Black Spinel « Aussie Sapphire[…]…

  9. Sisira says:

    I am Sri lanka i have Spinal 5-20 caret per stone any one interest pls e mail

  10. Wow..(Aussie Sapphire) look stunning, Thanks for sharing this information but here are lots of other gemstones by which you can benefits such as white sapphire, yellow sapphire, cats eye gemstone, check out their benefits and advantages at

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