Tourmaline is a popular semiprecious gemstone noted for it is wide range of colors. Think of a color and there will be a tourmaline somewhere to match it. What is a tourmaline? It is a boron aluminum silicate mineral of…
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The Cat’s Eye is a rare and striking gemstone, but what is it? Well, it looks just like a cat’s eye, cut en-cabochon, having an intriguing sharp silvery band of light that moves across a translucent honey yellow background when…
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Yes, Diamonique is good stuff in more ways than one. In fact, Diamonique is better than real diamond, and I shall explain why. What are we talking about? Diamonique, aka Diamonte, aka Diamonite are trade names for the wonderful gemstone made…
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What is a dichroscope? The word really means “to see two colors”. The use of a dichroscope can be helpful in identifying colored gemstones. Also, faceters of gemstones may find one useful for favorable orientation of rough crystals. Gemstones which…
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The “Chelsea Colour Filter” is a dichromatic filter which transmits deep red light, ca 690 nm and yellow green light, ca 570 nm wavelengths (nanometres). It was developed (1934) in the Gem Testing Laboratory of the London Chamber of Commerce…
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A loupe is a jeweler’s name for a little magnifying glass of about 10x power. Of more general use is a combination double hand lens set of 10x and 20x magnification used by gem and mineral enthusiasts and field geologists….
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The garnet family of gemstones is unusual in that it shows a wide range of chemical composition and yet retains the same crystal structure. Garnets have cubic symmetry and consequently are isotropic and show no dichroism. The most common color…
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Fine green jadeite can command exceptional prices. Christies auctioneers have sold jade jewelry for millions of dollars. When investing this sort of money in jewelry it is essential to know that you are buying the real thing. A better question…
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Peridot is a little known semiprecious gemstone that really deserves more attention. Peridot is the name given to gem quality samples of the mineral olivine, which is a common rock forming mineral found in volcanic rocks. Its chemical composition is…
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Pablo Neruda, the Chilean Nobel Prize winning poet, wrote in his poem “Las Piedras del Cielo” about his love of gems and minerals: Cuando se toca el topacio, el topacio te toca or, when you touch the topaz, the…
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Where do rubies and sapphires come from? Most people would buy gemstones set in a ring at a jewelers, and think nothing more about it. The jeweler buys stock from a manufacturing jeweler, who buys the gemstones from a gem…
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The electronic diamond tester is the latest gadget for testing of gemstones. Every gemstone enthusiast or gem dealer should have one. But what is it and how does it work? What are its capabilities? By name it suggests that by…
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What does the word “Paraiba” mean in the gem and jewelry markets? The word “Paraiba” is frequently used today to describe a gemstone but what does it mean and what is its origin? Paraiba is a State of Brazil located…
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Loose gemstones are much easier to identify than those set in jewelry because you are able to do more tests unencumbered by the setting. Firstly you do an eye-ball inspection of the loose gem, which may be faceted or cut…
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Tanzanite is one of the new exotic gemstones to come onto the market. This striking purplish-blue gemstone variety of the mineral zoisite was discovered in 1967 in Tanzania, East Africa. The mine site is at the base of Africa’s highest…
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Some gemstones will fluoresce when illuminated by blue or ultra violet light. This can be an aid to their identification and provenance. The fluorescence appears as a glow of a color having a longer wavelength than the impinging radiation, thus…
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Emeralds have been known and treasured since prehistoric times. The ancient Egyptians began mining emeralds from a deposit in the Eastern Desert near the Red Sea during the 12 th Dynasty (1991 – 1778 BC), a region which much later…
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A diamond simulant is something that looks like a diamond but isn’t. It can be a manmade material or a natural gemstone. For example, a faceted manmade glass gem (called paste by jewelers) is a diamond simulant when made colorless…
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Emerald green is a color many admire and desire to have amongst their jewelry. Natural emeralds are noted for their distinctive color which ranges from a yellowish green to grassy green and bluish green, usually showing some dichroism within this…
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The gemstone region of East Africa is exotic and relatively new compared to the long established gemstone regions of South East Asia and Brazil. It extends from the island of Madagascar (Malagasy) in the Indian Ocean to mainland Mozambique then…
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Emeralds have been prized by man and worn as adornment by women for several thousand years. Cleopatra loved emeralds which conveniently were mined close to home from the Red Sea deposits. This lively green gemstone was fashioned into beads and cabochons…
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Synthetic ruby, by definition means one made by man, whereas a natural ruby is found in Nature. It is as simple as that, but it is usually difficult to tell the difference with a faceted gem, which can be a…
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Gemstones from Zambia and Zimbabwe Zambia, a central landlocked African country, now supplies to the international market a substantial range of fine gemstones, in particular emeralds, aquamarines and other beryls, tourmalines and amethyst. Zambia rates after Colombia and Brazil as…
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Amethyst and citrine are favorite faceted quartz gemstones used in jewelry. They are not too expensive so it may come as a surprise that manmade equivalents can be bought on eBay. How good are they? How might one tell the…
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Jet is a special kind of black fossilized wood which is carved and polished for jewelry. The most famous is that found at Whitby in North Yorkshire. The wood is thought to be that of an ancient araucaria pine tree,…
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Why are natural emeralds so rare in occurrence compared to beryl and aquamarine, which are the same mineral but a different color? Why are beryls and aquamarines found in pegmatite deposits but rarely so are emeralds? If you are a…
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A wire ring is the easiest ring to make. It is fun to do and can be made in 15 minutes. They are delicate and look exotic when combined with a wide range of gemstone and artificial beads. Only a…
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The most expensive gemstones are those we group as “precious” which includes natural diamond, emerald, ruby and sapphire. They sell at a premium because of their rarity for fine examples. All other gemstones are considered semiprecious and are less expensive…
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We all love aquamarine that gemstone sometimes found as flawless crystals having a sky blue color ranging to a green blue of the deep ocean. Its name comes from the Latin “aqua” (water) and “mare” (sea). In ancient times blue-green…
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Natural alexandrite is a rare variety of chrysoberyl, which is a beryllium aluminum oxide mineral. It is unique by showing both green and reddish-mauve colors caused by a trace amount of chromium. Alexandrite exhibits this color change depending on the…
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