Information
INTRODUCTION PERIDOT
An attractive stone , Peridot is the gem variety of the mineral olivine. A gem beloved by the Victorians, It is a yellowish-green in light and dark shades, some brownish .It is found in volcanic areas, commonly in basalts. The classic locality is St John’s Island in the Red Sea, but it is also found in Arizona, Hawaii, Tanzania, China, Vietnam and the Canary Islands. Those from Hawaii sometimes contain inclusions of petrol. Peridot rates 6 ½ on the Mohs scale, just below the recommended 7 for use in jewellery. Therefore it is liable to scratching or other damage if mounted high in a ring. Larger stones are to be preferred as the smaller ones fail to show the density of colour.
Peridot was frequently foil backed in antique jewellery to improve the colour of the lighter stones. Glass imitations are found ,but do not show the double refraction of the natural stone. A convincing synthetic corundum simulant of Peridot is now on the market. This was the favorite stone of the pirates as they believed that it would protect them against all forms of evil and ,if set in gold ,would save them from the terrors of the night. It was supposed to strengthen eyesight ,as well as the heart and respiratory tract. It was also supposed to relieve depression and even protect against baldness.
VALUE
Peridot ranges in price from about $50–80/ct. for well-cut gems in the 1–2 ct. size, up to as much as $400–450 ct. for large fine gems of top color.Visit our dubai online shopping and we can assist you with the right information about the value of Peridot and about any other gold stones.
PERIDOT GEMSTONE PROPERTIES
Composition | Peridot is the gem variety of the olivine group, which has the following species: Forsterite–Mg2SiO4 |
Hardness (Mohs) | 6.5 to 7 |
Cleavage | Imperfect to distinct in one direction (rarely seen) |
Specific Gravity | 3.34 + 0.17,–0.07 |
Refractive Index | 1.654–1.690 (±0.020) |
Birefringence | 0.035 to 0.038 |
Optic Character | Biaxial (positive or negative; the beta index is usually near halfway between alpha and gamma) |
Crystal System | Orthorhombic; usually occurs as rounded pebbles; well formed crystals are quite rare. |
Colors | Mainly green; sometimes yellow or brown |
Pleochroism | Weak to moderate, dichroic |
UV Fluorescence | Generally inert |
Dispersion | 0.020 |
Phenomena | Cat’s eye and star peridot are known, but are rare |
Handling | Ultrasonic: not safe; never clean peridot ultrasonically Steamer: not safe The best way to care for peridot is to clean it with warm, soapy water. Avoid exposure to heat, acids and rapid temperature changes. |
Enhancements | Peridot is not typically enhanced. |
Synthetic available? | No |