RubY

Ruby is the red and most valuable variety of the mineral species corundum. Fine stones over 2 carats are rare and expensive. Ruby is the July birthstone and is used for the 40th wedding anniversary. Major sources are Thailand, Burma, Kampchea, Sri Lanka and Kenya. Others are India Pakistan and Tanzania.

In ancient India ruby was called the "king of gems". Wearing ruby was once thought to bring wealth, health, wisdom, and success in love. Worn in a ring on the left hand or in a brooch on the left side, it gave the ability to live in peace among enemies. The Burmese thought a ruby inserted in a warrior's flesh made him invincible.

Trade Names

• Burma-red to slightly purplish red in medium dark tone and vivid saturation;generally considered finest color and denoted by the term pigeon's blood
• beef blood-slightly darker than pigeon's blood color
• Thai-dark red to brownish red or purplish red
• Ceylon or Sri Lankin-lighter in tone, and often more brilliant than Burmese of Thai stones
• African-typically orangy red
• star ruby-semitransparent to opaque with asterism (usually 6 rays)

Identification

• Optic Character: DR,uniaxial negative
• Refactuive Index: 1.762-1.770 (+.009,-.005)
• Specific Gravity: 4.00
• Identifying Characteristics: silk(fine needle-like rutile or boehmite crystals);rutile needles often arranged in three sets that intersect one another ar 60 degree angles;fingerprint inclusions,hexagonal growth lines and color zoning.

Care And Durability

• Cleaninng Methods:
  • ultrasonic: usually safe,but never for oiled stones
  • steamer: usually safe,but never for oiled stones
  • warm soapy water: safe
• Hardness: 9
• Stability
  • Reaction to Heat: sometimes improves color
  • Stability to Light: stable
  • Reaction to Chemicals: attacked with difficulty