Sapphires
One does not need to know all about sapphires but it is a good idea to know as much as possible about them so you can adequately chose a sapphire for ones own.
The word Sapphire apparently comes from the Hebrew ‘Sapir’ but may also have origins from the Greek/Sanskrit ’sanipriya’, meaning “dear to the planet Saturn”. A sapphire is a single-crystal form of aluminum oxide, a mineral known also as corundum. It can be found naturally as gemstones or manufactured artificially.
It is the small trace elements of iron, chromium and other minerals that give sapphires their blue, red, yellow, pink, purple, orange or greenish color. Sapphire includes any gemstone quality varieties of the mineral corundum including the red variety, also known as ruby. Both Sapphire and Ruby have a hardness of 9 on the Mohs Mineral Hardness scale, just below diamond which is classed as 10 on the scale.
According to Wikipedia:
“Blue sapphires come in a wide range of shades of blue. Titanium and iron inclusions within the aluminum oxide result in various shades of blue. Some stones are not well saturated and show tones of gray. About 99 percent of all sapphires are heated to a temperature of 3000 degrees C to give the stone a better color of blue. On magnification the silk due to included rutile needles are visible. If the needles are unbroken, then the stone was not heated. If the silk is not visible then the stone was heated adequately. If the silk is partially broken then a process known as low tube heat was used. Low tube heat is the process where the rough stone is heated to 1000 degrees C for 10 to 20 minutes. This takes out any gray in the stone and improves color saturation.”
“Fancy sapphires are any sapphire other than blue or red. Purple sapphires are lower in price than blue ones. These stones contain the trace element vanadium and come in a wide variety of shades. Yellow and green sapphires have traces of iron which gives them their color. Pink sapphires are have trace element of chromium and the deeper the color pink the higher the value as long as the color is going toward red of rubies. Color shift sapphires are blue in outdoor light and purple in indoor light. Some stones shift color well and others only partially, in that some stones go from blue to blue purple. White sapphires usually come out of the ground as light gray or brown and are then heated to make them clear. However in very rare circumstances they will be found in a clear state.”
Sapphires are mined mainly from alluvial deposits or from primary underground workings. Historically, most sapphires have been mined in Sri Lanka, Madagascar and Myanmar. Australia, however, now leads the world in sapphire production producing sapphires from basalt derived deposits in the north east of the country, Queensland and New South Wales. Pakistan, Afghanistan, India and Kenya also produce sapphires although not in any great quantity.
Studying up so one knows all about sapphires is an excellent way to be knowledgeable before you start to go off and buy a sapphire.