Pakistan gem safariWritten by Alain Darbellay GGGems
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deposit of natural cherry topaz in world. -------------------------------------------------- · Emerald from Mingora, main city of Swat. The deposit discovered in 1958 was closured and monopolized by government, it is what compelled certain inhabitants residing in neighborhood to dig under their house in order to research prohibited treasure. TECTONIC CONTROL OVER EMERALD MINERALIZATION IN SWAT. It is in Swat valley that Alexander of Macedon fought Emerald and chromian tourmaline occur in carbonate-talc/ and won some of his major battles before crossing over serpentine/chlorite rocks, carbonate-bearing talc schists, to plain of Pakistan. and associated quartz veins near Mingora, Charbagh, and Let us note that emerald was known for a long time Shangla. The rocks are altered ultramafics found in a in this valley, thanks to an analysis on a stone of a discontinuous belt of volcanic, volcano-sedimentary, and Gallo-Roman ear-ring, witch shown that this emerald sedimentary rocks that have undergone high P-low T originated in of mines located in Swat valley. metamorphism. This thanks to measurement of report/ratio of This is at occasion of one of our visits in valley, that some children tolled us that they found some fragments of emerald in Swat river. concentration of isotopes 18O and 16O. Indeed, isotopic composition out of oxygen of this precious stone is dependent on that of rock where it crystallized. · Central street of Mingora. ------------------------------------------------- Blue-green tourmaline from Kunar valley, Afghanistan. Nimak mendy, old Peshawar, on road to Afghanistan. Mountains of Afghanistan. Alain talking with our Afghan friend Sarbaz. GGGEMS.COM © 1987 - 2004 gggems.com All rights reserved.
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| | Discovery of Pyrope Spessartite garnets ( Madagascar )Written by Alain Darbellay GGGems
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At this time started orange garnet's fever. The stone did not show almost any more change, its champagne-orange color at day was simply reinforced in a vivid orange or for other elements in an orange-red under electric light. This type of garnet is a pyrope-spessartite also containing vanadium and chromium traces. On totality of Malaya extracted, a small part was pure, but much showed typical inclusions of this stone. Initially networks of rutile needles and strain patterns were often present, and inclusions of graphite accompanied them. Negative crystals and, quartz, apatite, monazite and zircon had been also invited during growth of precious malaya garnet. Here first pyrope-spessartite cut in 1998. Realized in an arid landscape composed of bushes and cactus, this discovery remains exceptional by quality of its product and also by fact that it was second deposit in world to deliver this type of Malaya garnet. Here, one of only intact garnets found in occurrence. Its unusual stacking shape must be noticed. Refractive Index: 1.73 - 1.81 Chemical Composition: [Mg3 + Mn3]AL2(SIO4) Hardness: 7 - 7.5 Density: 3.65 - 4.20 Crystal Group: Cubic Above, only phlogopite mica found in neighborhood of deposit at that time, it is still in its gangue. Of transparent quality, it shows a similar color to that of malaya garnets. ¦ Garnet data ¦ Madagascar Gem Safari ¦ Malaya garnet Catalog ¦ All pictures on this site have been shot by gggems.com Alain Darbellay © 1987 - 2004 gggems.com All rights reserved.
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