per·i·dot
Peridot is a gemstone with a fascinating history, both in nature and culture. It is one of the oldest known gemstones, with ancient written records documenting the mining of peridot as early as 1500 B.C. It is a gem especially connected with ancient Egypt, and some historians believe that the famous emeralds of Cleopatra were actually peridots.
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Tradition says you will be able to successfully ward off evil, enchantments and depression if you wear or carry peridot.
Periodot is associated with the heart chakra, and can be used to balance and stimulate that chakra. It is a stone of compassion. It has a friendly energy and is excellent for healing. It assists in rebirth and renewal of all kinds. Peridot also bring abundance and prosperity. It enhances the healing and harmony of relationships of all kinds, but particularly marriage. Peridot is used in crystal healing to lessen stress, especially in relationships, anger and jealousy, slow aging, and heal ulcers and digestive problems. Please note that healing crystal meanings are spiritual supports to healing and are not prescriptions or health care information. It also assists in finding what is lost, and strengthens ESP abilities. It has been said to make a shield of protection around the body of any wearer of peridot. (
http://meanings.crystalsandjewelry.com/peridot/
The Color intensity depends on the amount of Iron present in the chemical structure; the more iron the deeper green it will be.
Chemical Formula: (Mg, Fe)2SiO4
Color: Green, Yellow
Hardness: 6.5 - 7
Crystal System: Orthorhombic
Mineral Class: Olivine
(http://www.minerals.net/gemstone/peridot_gemstone.aspx)