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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: Jade
…high polish. Nephrite is commonly found in a darker olive green color but can also be very light green, orangey-red, black, and yellowish green. Jadeite can come in many different colors including pink, purple (often called lavender jade…
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Gem in the Spotlight: Alexandrite
… in jewelry such as earrings or pendants that are less prone to impacts than rings, for example. Alexandrite 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-change itself is often called “The Alexandrite Effect.” Stunning color change on a natural alexandrite. Alexandrite History and …
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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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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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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 …
