Blue Spinel

Blue Spinel is a naturally occurring colour variety of Spinel, a mineral belonging to the Spinel Group. It is composed mainly of magnesium aluminium oxide and can occur in a range of blue shades, from pale grey-blue and violet-blue to vivid cobalt blue. Its colour is commonly caused by trace amounts of cobalt, iron or a combination of colouring elements incorporated into the crystal structure during growth. Fine cobalt-rich Blue Spinel can display an intense, highly saturated blue and is particularly valued as a gemstone. Spinel forms in metamorphic rocks and in some igneous environments, and gem-quality crystals are also recovered from secondary gravel deposits after erosion releases them from their original host rock. Blue Spinel is durable enough for jewellery and has a high lustre and strong brilliance when cut. Natural Blue Spinel should not be confused with synthetic Spinel, which is widely manufactured and can be produced in very vivid blue colours.