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Fine Jewelry University Articles matching: “Black tourmaline”
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Fine Jewelry University
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Gem in the Spotlight: Emerald
… found. What sets trapiche emeralds apart from other emeralds is their unique growth habit, featuring six black spokes radiating from a hexagonal core. This distinctive pattern is believed to form due to interruptions in the crystal growth…
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The Magic of Polarized Light
…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 far the most …
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Gem in the Spotlight: Amethyst
…, but it can also be 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…
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Gem in the Spotlight: Pearl
… quality, and today they are very difficult to tell apart from their saltier cousins. Tahitian Pearls: Also known as black pearls, Tahitian pearls are a type of saltwater pearl that are grown primarily in French Polynesia. They are known … rainbow colors that shimmer on or just below a pearl’s surface). Pearls come in a range of colors, from white to black, with many shades in between. The most valuable pearls are those with a pure, even color, such as white, pink, or …
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What to Do When Your Ring Irritates Your Skin
… which can begin hours or even days after contact and may last for several weeks. Some people’s skin even turns black or green when they wear certain jewelry. One of the most common metal allergies is Nickel which is added to pure gold in … a simple discoloration on top of the skin from the metal. Also, tarnish from silver jewelry can rub off and leave a blackish residue. In both cases, the color will easily wipe or wash off. You can avoid this type of discoloration simply …
