indian astrology gemstones

Precious and semiprecious stones are mineral aesthetics , the result of cutting and polishing processes developed are used for beautification jewelry. Tra***ional classification between precious and semiprecious stones appeared for the first time in ancient Greece , was then adopted by other cultures. Today, gemstones are treated diamond, ruby , sapphire and emerald , while others are semi , but this distinction is unscientific and reflects in particular rarity and hardness gems ( depending on the position on the Mohs scale ) . The experts , in turn, classified according to chemical composition gemstones , crystal system and the environment in which they formed . Gems are characterized by refractive index , light scattering , hardness, cleavage , diaclases and gloss . Color is an important element of differentiation gems by color intensity or optical effects . The alexandrite , for example, green and red purple daytime night labdradoritul delight in effect irizatie ( a play of light due to light refractories ) and tourmaline has two or three colors in the same rock , the most common combination being the pink and green buy gemstones. Also , jewelery ornaments can be embellished using organic nature , and in this category mention pearl , pearl, coral , amber , to 74656
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