Precious stones are the most beautiful and valuable of all the gemstones. Their colors are vibrant, translucent and brilliant. These natural crystals are also durable, but at the same time rare, and they can be used to create both jewelry and accessories.
Spinel is the magnesium aluminum member of the larger spinel group of minerals. Its hardness is 8, its specific gravity is 3.5–4.1, and it is transparent to opaque with a vitreous to dull luster. It may be colorless, but is usually various shades of red, blue, green, yellow, brown, or black.