MRS. SEEMA A. ATHAVALE
CHIEF GEMOLOGIST, GSI
M.Sc., D.G. FGA (UK),
GRADUATE PEARL GIA (USA),
Marine water pearl culture technician, Tuticorin (CMFRI), Tamil Nadu, India.
According to the ancient scripts of Sanskrit, both kuruvinda and padmaraga are names for ruby. Kuruvinda refers to rubies of inferior color and clarity while padmaraga denotes rubies that possess the finest (purest, unmixed) color and top crystal clarity. Rubies of the finest quality are called padmaraga or lotus-hued while poorer quality rubies are referred to simply as kuruvinda or corundum. It may also be noted here that the English name for corundum was derived from the ancient Sanskrit word kuruvindam.
The name Ruby is derived from the Latin word ruber meaning “red.” Ruby is available in the color ranges from bright red to dark reddish-brown. Ruby is also known as Ratnaraj or the King of Gemstones.
Ruby is the gemstone of the Sun or Surya Graha as known in Vedic Literature.
Ruby is the birthstone for July as per the International calendar.
The prices of rubies are primarily determined by its color. Ruby is the most valuable of all gemstones.
*Ruby is the red variety of Corundum (Aluminum Oxide)
Rubies are found in metamorphic rock types such as gneiss and schist; and alluvial gem gravel deposits mostly.
Australia, Kenya, Madagascar, Myanmar (Burma), Tanzania, Thailand (Siam), Sri Lanka (Ceylon), Afghanistan, Tajikistan, Vietnam, India etc.
Ruby is a relatively hard gemstone i.e scratch resistance. It stands at 9 on Mohs scale of relative hardness. Ruby has excellent toughness i.e when it is struck it does not break easily. So it makes great choice for daily wear especially in rings.
Ruby Simulants or Look-a-Like:
Spinel, Red glass, Rubellite (Red Tourmaline), Almandine –Pyrope garnets
Three important quality factors that affect the value are color, clarity and quality of cut. Ruby with high clarity, rich color and good cut fetches more value.
Care and Caution:
- Avoid direct heat if it is filled with artificial material
- Avoid using acids on fracture filled rubies
- Avoid using ultrasonic and steam cleaners if stone is heavily fractured or lead-glass filled
- Ultrasonic and steam cleaners are usually safe for untreated and heat-treated stones
- Avoid polishing coated stones
- Fracture or cavity filled rubies and dyed rubies can damaged by mild acids like lemon juice so such material should be cleaned with a damp cloth only
* A reputed gemological lab can advise if the material has been treated
To improve the quality of its color, rubies are commonly heat treated. This treatment removes brown and blue tones from stones.
Fractures and cavities may be filled with an artificial material as result of the heat treatment process.
Because of their poor clarity, Indian star rubies they are often dyed and oiled.