BLACK TOURMALINE CABOCHON 925 STERLING SILVER JEWELLERY
The tourmaline gem family has a wide variety of components, even though tourmaline itself is a boron silicate mineral. Tourmaline crystals may develop in a greater variety of colours than any other gem can, and their crystal structures are very similar. However, because of the significant variation in the chemical composition, three distinct species have been identified: schorl, dravite, and elbaite.
The state of Maine in the United States of America recognises tourmaline as their official state mineral. One of the hardest gemstones is black tourmaline. If you aren't sure if your stone is tourmaline, you can do a scratch test to see if it's the real deal. Hard plastic can be scratched with a sharp needle, but not tourmaline. Natural black tourmaline can be challenging to mark with an arrow. Therefore it is unlikely that the stone you are looking at is one.
Origin: United States. Colour: Black and verities of colour Clarity: Translucent. Cuts: Slices. Treatment: Untreated 100% Genuine Gemstone.