Olivine/ Peridot

  • OlivineWhat is it and where is it formed?  Olivine is sometimes called peridot [peary-doe] by jewelers.  It is the birthstone for August.  It is a gemstone.  Olivine is formed in igneous and metamorphic rocks.  Olivine has iron and magnesium in it and the amount of iron decides what color the stone will be. 

  • How and where is it mined?  Olivine is mined using underground mining.   It is mined in Egypt, Pakistan, Australia, and the United States [Arizona and New Mexico].

  • What is it used for?  Olivine is used for mineral collections, gemstones, and in industry for products that need to take a lot of heat.  Transparent ones are used for jewelry.

  • Interesting information:

    • Olivine does not cost a lot of money.  Dark green ones cost the most. 
Mineral Characteristic What the
mineralogists say		 Kid's Guide:  What it REALLY means!
Chemical Symbol Mg2SiO4

It has oxygen, magnesium, silicon, and iron in it.
Color Light olive green to pale yellow-green; colorless This stone is most often pale yellow but can be found in olive green [olivine] or colorless kinds.
Streak white When the stone is used to scratch a white plate, the dust that comes off of it is white.  This is the color of the powder if the stone was crushed.
Transparency Transparent to translucent You can see through some stones and others are blurry to look through.
Luster Vitreous It shines like glass.
Cleavage Poor in two directions. If you hit this stone with a hammer, it would not split easily.
Fracture Conchoidal When it breaks, the surfaces are smooth and shell like.
Magnetism None It is not attracted to, and will not attract, a magnet.
Hardness 6.5 - 7 It can scratch glass which makes it a very hard mineral.
Specific gravity 4.0 It is an average weight.
Crystal Shape Orthorhombic

Orthorhombic