Gems In Sri Lanka

• Sapphire

Sapphire is an aluminum oxide. Its colour varies from very light to dark blue to violetish-blue, bluish-green, yellow, slightly reddish-orange, brown, nearly opaque black, colourless, pink, violet and the pinkish-orange padparadscha (lotus flower).
Varieties
Coloured varieties, star sapphire, alexandrite-like sapphire.

Sources
Sri Lanka, Kashmir (India), Burma, Thailand, Australia, Tanzania, Kenya, Montana, Madagascar

Toughness
Excellent, except in laminated or fractured stones.


Precautions
Sapphires may fade if heated

• Ceylon Sapphires

The Ceylon Blue Sapphire is known for its beauty ? possessing the glorious cornflower blue shade ? as well as for being one of the few sapphires in the world that can be sold as a completely natural stone without heat treatment. The blues aside, Ceylon sapphires also come in beautiful hues including pink, yellow, orange, green, purple, lavender and of course, the inimitable padparadscha sapphire ? named after the lotus flower. All these highly marketable qualities of Ceylon sapphire has created brand recognition world wide - a brand not created by the producers of the stone, but by the sellers and consumers.
Sapphires that show a star-like light effect are called star sapphires; the most famous star sapphire from Sri Lanka is displayed in the Museum of Natural History in New York. Star sapphires or star rubies display a star-like marking and this effect, commonly known as asterism, occurs when light falls on the cut stone, cut in the cabochon form, and three rays appear giving a six-point star. However, stones with six rays have also been known to occur.

• Ruby

Ruby is an aluminum oxide, a variety of corundum; it occurs in medium to dark tones of red and violetish-red to brownish-red

Varieties
Star ruby
 
Sources
Sri Lanka, Burma, Thailand, Africa (Kenya, Madagascar, Tanzania), India.
 
Toughness
Excellent, except in laminated or fractured stones.
 
Treatments
The Burmese believed that "blazing red" stones could be found in a "bottomless" valley. Natives threw pieces of meat into the valley, hoping that some stones could then be recovered by killing the vultures. In the Royal Collection of England, you can view a gold ring set with a pale but nearly flawless ruby into which a portrait of Louis XII of France is carved.

Cuts & Uses
Faceted or en cabochon, usually mixed cut (brilliant crown, step-cut pavilion), beads, carved (poor quality).

Choosing a Ruby
The most important factor in the value of a ruby is colour. The top qualities are as red as you can imagine: a saturated pure spectral hue without any overtones of brown or blue. The word red is derived from the Latin word for ruby, ruber, which is derived from similar words in Persian, Hebrew, and Sanskrit. The intensity of colour of a fine ruby is like a glowing coal, probably the most intensely coloured substance our ancestors ever saw. It is no wonder they ascribed magical powers to these fires that burned perpetually and never extinguished themselves.

• Logan Blue Sapphire (423 carats)

Considered to be the second largest blue sapphire in the world on record. A flawless specimen with a rich deep blue, the stone was gifted to The Smithsonian Institute in Washington DC by John Logan.