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Fine Jewelry University Articles matching: “sapphire necklace”
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Gem in the Spotlight: Alexandrite
Emerald by day, ruby by night, more expensive than diamond and more illustrious than sapphire, emerald, or even ruby, alexandrite has been known around the world as one of the most sought-after gems for the … isn’t the only stone to display color-change phenomena. There are color-change varieties of many gems including sapphire, tourmaline, spinel, garnet, etc. Alexandrite is, however, the most famous for it. It is so famous, in fact, that color-…
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Gem in the Spotlight: Iolite
…near the top of the list. Iolite’s color range of blue, blue-violet, and violet competes for public attention with sapphire, tanzanite, and amethyst. They may have name recognition, but iolite has a rich, unique color and great gem value on …. The Gemology of Iolite Iolite is the gem variety of the mineral Cordierite. Iolite was once known as a “water sapphire”. Dichroite is another synonym for iolite. Dichroite is a Greek word which loosely translates as two-colored rock. This …
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Gem in the Spotlight: Amethyst
… found in smaller deposits in other countries such as Russia, the United States, and Canada. Amethyst is known for its durability with a Mohs hardness rating of 7. For reference, amethyst is roughly as hard as tourmaline, softer than sapphire and topaz, and harder than opal and tanzanite. This makes it a durable gemstone that is resistant to scratching and chipping. It is also resistant to heat and chemicals which means that it can withstand daily wear and tear. Amethyst …
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Gem in the Spotlight: Opal
…a refractive index of 1.37 – 1.47 and a Mohs hardness of 5.5-6. This makes it one of the softest gemstones commonly used in jewelry. For reference, here are the Mohs hardness values for some other gemstones you may know: Diamond 10, Sapphire 9, Amethyst 7, and Peridot 6. Turquoise is about as hard as opal, but you would need to consider Pearl or Amber (both 2.5) to find a commonly used gem that is softer than opal. Common Opal Treatments There are several different …
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Gem in the Spotlight: Topaz
… preference. Topaz itself is a hard gemstone with a Mohs hardness of 8. Mohs hardness is a standardized metric of how difficult it is to scratch something. For reference, topaz is a bit softer than diamond which is a 10 and corundum (sapphire/ruby) which is a 9 on the scale. It is a bit harder than emerald at 7.5-8 and quartz which comes in at 7. Here are some more gemological stats for reference: Refractive index: 1.619 to 1.627 Birefringence: 0.008 to 0.010 Specific …
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Gem in the Spotlight: Aquamarine
… in shades of blue-green. Aquamarine has a refractive index of 1.577 to 1.583 and is doubly refractive. Aquamarine’s specific gravity is 2.72 and it has a Mohs hardness of 7.5-8.0. For comparison, this means that it is softer than Sapphire, harder than Quartz, and similar to Topaz. This makes it a very durable stone that is suitable for regular wear. But, care should still be taken to ensure that the stone is not damaged. Caring For and Cleaning Aquamarine To maintain the …
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The Magic of Polarized Light
…gemstones, due to their unique chemical structure, actually polarize light themselves. These gems are doubly refractive (DR) and they will split incoming light in multiple directions. Some common examples of doubly refractive gems are sapphire, tourmaline, and moissanite. These are contrasted with singly refractive (SR) gems like diamond that only bend light in one direction. Gemologists use the term birefringence to refer to how doubly refractive a particular gem is. By …
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Gem in the Spotlight: Quartz
… Bloodstone Green jasper dotted with bright red spots Carnelian Reddish orange chalcedony Gemology of Quartz Quartz is known for its durability with a Mohs hardness rating of 7 (harder than opal and peridot but softer than topaz or sapphire). This makes it a fairly hard gemstone that is resistant to scratching and chipping. It is also resistant to heat and chemicals, which means that it can withstand daily wear and tear very well. All quartz has the same refractive index at…
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Gem in the Spotlight: Tanzanite
…, even with its rarity and dynamic look, tanzanite is still less in price than more commonly known gems like rubies, sapphires, and emeralds. Gemology of Tanzanite Gemologists refer to this gem as blue zoisite. The vast majority (current … its color. Tanzanite has a Moh’s hardness of 6-7, making it about the same hardness as quartz, softer than ruby, sapphire and emerald and hard than opal. Tanzanite has a refractive index of 1.69-1.70. History and Lore of Tanzanite Tanzanite …
