Sunday, 11 June 2017

Peridot

Peridot is gem-quality olivine, which is a silicate mineral with the formula of (Mg, Fe)2SiO4. Peridot is one of the few gemstones that occur in only one color: an olive-green. The intensity and tint of the green, however, depends on the percentage of iron that is contained in the crystal structure, so the color of individual peridot gems can vary from yellow, to olive, to brownish-green. In rare cases, peridot may occur in a medium-dark pure green.
Olivine in general is a very abundant mineral, but gem quality peridot is rare. This is due to the mineral's chemical instability on the Earth's surface. It's mohs scale hardness is 6.5–7, making peridot suitable for most jewellry.