Sapphire facts
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| Sapphire earrings |
- Sapphire is a gemstone variety of the mineral corundum, an aluminium oxide (α-Al2O3), when it is a color other than red, in which case the gem would instead be a ruby.
- Sapphire has been treasured for thousands of years. The ancient Persians believed that the earth rested on a giant sapphire and its reflection colored the sky.
- Mohs scale hardness 9.0
- Because it is a gemstone, sapphire is commonly worn as jewelry.
- The Tradition holds that Moses was given the ten commandments on tablets of sapphire, making it the most sacred gemstone. Because sapphires represent divine favor, they were the gemstone of choice for kings and high priests.
- The cost of natural sapphire varies depending on their color, clarity, size, cut, and overall quality as well as geographic origin.
- Sapphire has long symbolized truth, sincerity, and faithfulness.
- Color in gemstones breaks down into three components: hue, saturation, and tone.
- Hue is most commonly understood as the "color" of the gemstone. Saturation refers to the vividness or brightness or "colorfulness" of the hue, and tone is the lightness to darkness of the hue.
- Sapphire was thought to have strong medical powers. At one time it was credited to remove all impurities and foreign matter from the eye.
- The 423 carats (85 g) Logan sapphire in the National Museum of Natural History, Washington D.C. is one of the largest faceted gem-quality blue sapphires in the world.
- The British Crown Jewels are full of large blue sapphires, and even more recently Prince Charles chose a sapphire engagement ring for Princess Diana.
- Padparadscha is a pink-orange corundum, with a low to medium saturation and light tone, originally being mined in Sri Lanka, but also found in deposits in Vietnam and Africa; Padparadscha sapphires are very rare and highly valued. The name derives from the Sinhalese word for lotus blossom.
- Sapphire is the birthstone for September, but ancient lists also name sapphire as a birthstone for April and the gemstone for the sign of Taurus.
- The Black Star of Queensland is believed to be the largest star sapphire, weighing in at 733 carats.
- The ancients regarded star sapphires as a very powerful talisman, a guiding star for travelers and seekers of all kinds.
- The Star of India (563.35 carats) is thought to be the second largest star sapphire and is currently on display at the American Museum of Natural History in New York City.
