Those Color Change Stones ! Surprise Someone !

Wear the same necklace or earrings in the daytime, or at night, in florescent lighting or incadescent lighting and make people think you have a whole wardrobe of jewelry. Most people that have ever had anything to do with gemstones are aware that certain stones change color under varying light conditions. Many of these color differences are apparent only to the trained eye, but the so-called "color-change" gems exhibit this tendency to such a dramatic degree that it is obvious to even the untrained eye.

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For most Alexandrite is the everyday example and all know the saying : Emerald by Day - Ruby by Night", greenish under daylight or flourescent light and reddish under incandescent light.

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Color-change Garnet changes from bronze in daylight to a rose pink under incandescent light.

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Although most Sapphires have some color change to them and why good Sapphire markets only trade during daylight, the color-change Sapphire exhibits a range of many different color changes. Most color change Sapphires are blue under natural light and purple under incandescent indoor lighting.

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But there is a fourth color-change stone that in sizes from 5 carats up, exhibits a raspberry red to leaf-green color change as dramatic and complete as that of fine Alexandrite. So why doesn’t this Turkish delight get the respect it deserves? It's true name is Turkish Diaspore. But recently it has been given a new name - Zultanite. This marketing name - Zultanite—a deliberate misspelling of Sultanite which was already the registered trade name for another Turkish product. One would think Turkish-sounding names like Ottomanite or Caliphanite would have done a better job of invoking Turkish history, than substituting a “z” for an “s”? In any case, Zultanite Gems LLC, based in Fort Lauderdale, FL, has been doing its best since 2005 to capture attention for this inexpensive, all-natural rare gem with a hardness between 6 ½ and 7, and minuscule yields of 3 percent from the rough. Maybe the fact that this company has the sole rights to mining of this gem at its only known source, some 4,000 treacherous feet up in the mountains of Anatolia, prevents others from joining the company in the promotion of this gem.

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So take a look at these pictures above and note that unlike other color change gems that need separate lighting environments to show their color states, this highly pleochroic gem can perform multi-colored wonders when cut with that purpose in mind.

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One other stone that must be mentioned at this point because of it's popularity is Zandrite. This stone is a type of synthetic glass that was developed by a major glass manufacturer. One of the developing scientists realized that there was a gemstone marketing application possible and started the ball rolling to create a new synethic gemstone sensation. Based on the reaction from the public, he was quite successful. Since Zandrite changes color is the reason for it being named Zandrite ... sort of a cutesy take-off on the name of Alexandrite. It was most likely an effort to fool the unknowing consumer who might mistake the Zandrite name with the Alexandrite name and think they were getting the real thing for pennies on the dollar compared. Zandrite is a man-made lab created stone that was specifically produced to mimic Alexandrite, an imitation not a synthetic, but in many settings is a beautiful gemstone in its own right. This mimicing went over so well, that there are now other color-changes available in Zandrite gems.

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And not to be left out, is the Russian Lab-created Alexanderite. Synthetic lab grown (created) Chrysoberyl Alexandrite gems many times exceed natural Alexandrites in clarity and color change, and since they are 'real' Alexandrites grown from seed stones, confuse even some of the best gemologists and jewelers. Synthetic lab grown gemstones are like comparing a rose grown outside to one grown in a greenhouse, both are the real thing - BUT ! Also be cautious when buying lab-created Alexandrite, because many dealers indiscriminately use the term imitations and are making reference to color-change Corundum, which Alexandrite is a member of the family, instead of stating it is synthetic Alexandrite. A fine line but a distinction that should be made and disclosed to customers.

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Additional Info --- I have been informed I left out color-change Tourmaline. I was unable to find any reference to such, but do remember hearing about it the Tucson Gem Fair. I do not have one or have I ever seen one. If anyone can provide a picture showing both colors I would definitely appreciate it.

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Thanks to the ISG, Zultanite Gems LLC and others for information and pictures of color-change gemstones.
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The Trapiche Gemstones !

Everyone should always keep their eye open for some of the neatest and fairly rare gemstones in existance --- the Trapiche Gemstones ! The Spanish word trapiche was used in Colombia with a literal translation that means 'wagon wheel'.

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It was and still is applied to a rare form of Emerald that has inclusions aligned along the edges where the crystal faces meet, which causes the stone to literally look like a wagon wheel. The most famous and best known is the 'Trapiche Emerald'.
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A Trapiche Emerald, found only in Colombia at Coscuez, La Peña in the celebrated Muzo mining district
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But......the trapiche 'wagon wheel' formations can indeed occur in other types of gemstones, i.e. Ruby, Sapphire, Tourmaline and particularly in a form of Andalusite. So the term 'Trapiche' must be clarified by adding the name of the Gemstone along with it.
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For insatnce Trapiche Ruby, of which there are two distinct types, one with the carbon 'wheel' from Viet Nam and the second with the lighter colored 'Calcite' or 'Dolomite' wheel' from the Mong Hsu region of Myanmar (Burma).
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A Trapiche Sapphire, probably of Burmese origin.
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A Trapiche Tourmaline, of this green variety, can be obtained from the Kavungu mine in the vicinity of Jivunda southeast of Mwinilunga in northwestern Zambia.
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A Trapiche Andalusite, called Chiastolite, has the same kind carbon spokes as the Emerald and Ruby. This particular form of Chiastolite is found in areas around Georgetown, California. It is also known to many as "The Cross Stone" in religious circles.

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And I have been told there is a Trapiche Garnet, but have never seen one or even a picture of one, so definitely something to look for.

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Pictures from own collection and those of some close friends. The locations indicated are where these particular speciems originated from.

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Vermont "Grossular Garnet" !

Vermont's Legislature designated the grossular Garnet as it's official state gem in 1991.

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Grossular or grossularite is a calcium-aluminium species of the Garnet group though the calcium may in part be replaced by ferrous iron and the aluminium by ferric iron. The name grossular is derived from the botanical name for the gooseberry, grossularia, in reference to the light green Garnet of this composition. Other shades include cinnamon brown (cinnamon stone variety), red, and yellow. The more common variety of grossular Garnets are called hessonite from the Greek meaning inferior, because of its inferior hardness to Zircon, which the yellow crystals resemble. Grossular Garnets, like other Garnets, form rounded crystals with 12 rhombic or 24 trapezoidal faces or combinations of these and some other forms. This crystal habit is classic for the Garnet. As stated, Grossular is the calcium aluminum Garnet and forms in contact or regional metamorphic enviroments as does andradite Garnet, the calcium iron Garnet. It is believed that these Garnets form from the metamorphism of impure siliceous limestones. Grossular has many color possibilities and is probably the most colorful of the Garnets. The orange variety is the most common and specimens of orange grossular crusts are prized by many collectors. The dark green variety is called tsavorite and is cut as a gem. Hessonite is a red to yellow variety of grossular and is also used as a gem.

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Windom and Lamoille counties are the primary locations for Garnets in Vermont, but collectors are reminded to obtain written permission to search for them on priviate property or old mine sites. Beautiful brownish-reddish grossular Garnets can be found near Mt. Belvidere, Eden Mills, Vermont.

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New York's "Garnet" !

The wine red variety of Garnet was designated the State gem of New York in 1969. Garnets have been considered precious for thousands of years and are found in early Egyptian, Greek and Roman jewelry. Red is considered the Garnet's principal color, but Garnets actually come in several hues, including various shades of green, a light to intense yellow, a fiery orange, and several earth-colored hues.

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The Barton Garnet Mine contains the world's largest Garnet deposit. The mine is located at the on top of Gore Mountain near North River, New York. Crystals of Garnet have been found here that are as big as 20" across. Collecting facet grade material is very easy, requiring little more than a hammer to break open the crystals and a watchful eye. Specimen collectors need to take more time to collect crystals intact. The mine is about four hours from New York City and offers a guided tour of their facilities. Mineral clubs must make arrangements in advance for mineral collecting at the mine.

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Deposits of industrial grade Garnet are found at two locations in New York. In the Gore Mountain area, industrial garnet is mined as the primary product; and near the town of Willsboro, byproduct of it is recovered as wollastonite mining. The deposit near Gore Mountain is an almandite-bearing diorite of uncertain, igneous or metamorphic origin. The Garnet is present as imperfectly developed crystals surrounded by a rim of coarsely crystalline hornblende. The crystals range from about 1 millimeter to almost 1 meter in diameter but average about 100 millimeters in diameter. The Garnet has a pronounced laminated structure, which enables it to naturally break into thin plates from about 2 to 6 millimeters in thickness. Garnet fragments maintain this platy particle shape even as they are crushed smaller and smaller. These same deposits in Warren County contain good to fine quality facet-grade Garnets. The Garnet is a solid solution of pyrope-almandite-grossularite that results in a pleasant deep brownish-red material which often has an orange cast. Beautiful small stones can be faceted, but larger stones are too dark to be attractive.

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Connecticut's "Garnet" !

The Garnet, normally considered a gemstone, was officially designated the state mineral of Connecticut in 1977. The Garnet “group” of gemstones is well known from many localities around the state. Both ornamental and functional, Garnet is readily identified by its small granular crystals, most often seen in a deep reddish brown color. Some of the finest almandine Garnet in the world is found in Connecticut. Garnet varies in color from pale to dark tints, including the deep violet-red of the almandine Garnet. Garnet is a hard mineral also used as an abrasive in grinding wheels, saws, and sandpaper, thus this mineral played an important role in the history of Connecticut industry.

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Garnets are a common constituent of the igneous rock pegmatite, and of coarse granite and granite gneiss. Garnets are also frequently found in mica schist, a common metamorphic rock. One can also find tiny garnets in beach sand and in sandstone deposits. Garnets are called a “group” because similar minerals of different chemical composition have the same atomic structure. The variety 'Almandine' is an iron aluminum Garnet. Other varieties found in the state include Pyrope, magnesium aluminum; Grossular, calcium aluminum; Spessartine, manganese aluminum, and Andradite, calcium iron. Transparent Garnets of good color can be cut as gemstones, but other than the 'Almandine' which is some of the best in the world, it is rare to find garnets of that quality in Connecticut, thus why the Garnet was named more as the States mineral rather than a gemstone. Most commonly, rough garnet is used as an abrasive, as in sandpaper and emory boards, a major industry in Connecuticut.

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Some of the best Garnets are found around Roxbury, Redding and Colchester. Greens Farm Garnet Mine is an old, classic location. Large almandine Garnet crystals to 1" across can be found in both hard rock or loose in the soil. The old mine dumps are also scattered around the woods and provide loose crystals without much work. Much of the matrix is very soft, but the best garnets are found in the harder schist. The mine is located in a rural area of northwest Connecticut, near West Redding.

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