Intro to sapphires, and how to buy them
Published On: 11-14-2011 06:55pm
Comments: 0 - Hits: 17
Sapphires form from the mineral corundum, and occur naturally in a variety of colors - blue, green, purple, yellow, white, and orange-pink padparadscha sapphire.Fairly new to the market are autumn-hued sapphires called tunduru or tundra sapphires - ranging in colors from cognac thru yellow and taupe. I have only seen them sold in small faceted rondelle shapes, not as single stones. The deep, velvety blue sapphires, so highly prized, come from the Kashmir region in India and from Burma. Rarely seen on the market today, their deep color is enhanced by rutile needles, called "silk", within the stones. Star sapphires are formed with these "silks" also, when they are aligned just right. Most of today's stones come from Burma, Sri Lanka, Madagascar, Kashmir, Australia, and Tanzania, although other countries also participate inthe marker to a lesser extent - Cambodia, China, Kenya, Nigeria and Montana in the U.S.
Sapphires (and rubies) are rated a 9 on the Mohs Hardness Scale which makes them the hardest stone after diamonds, and very suitable for jewelry applications.
I found some buying tips online and am passing them along to you. When buying sapphires, view them in good daylight or under flourescent light as that is where they will look best. Sapphires tend to be "cleaner" than rubies -(less inclusions) so look for stones that are "eye clean", meaning that you cannot see any inclusions when you look at them with the naked eye. If you are looking at blue sapphires, be aware that the very light stones and the very dark stones are not highly valued. Instead look for an intense, rich hue in the stone without its being dark or inky.
Know that most sapphires are heat-treated to enhance color, usually before they are cut. Ask if this is the case, as a natural, untreated blue sapphire will be much more valuable than a heat-treated stone. Some other treatments can also be applied to the stone, and these can also affect their value. Ask what treatments have been applied to the stone which you are considering.
There are some famous sapphires in the world - Diana Spencer and Kate Middleton's shared engagement ring pop into mind these days, because of the recent wedding of Kate and Prince William. Probably the largest sapphire gem is the 422-carat Logan Sapphire. Egg-sized and faceted in a cushion cut, set with 16 carats of diamonds and on display in the Smithsonian Museum of Natural History. It is pictured here for you from Wikimedia under the following permission: creative commons attribution-share alike 2.5 generic license by TomR.
