Have you ever wondered where the sparkling gems in your jewelry come from? For that matter, the pain and effort that it takes to bring those beauties to you?

Gemstones cover a long distance before they are actually fit for wearing as jewelry. Even after a gem is ready for sale it has to be placed and secured in metal to make jewelry that you ultimately buy from a store.

There are gem mines all over the world (except pearls and corals which comes from the water source) and some countries are known for the type of gems mined there. For example, ruby mines of Burma and diamond mines of South Africa. Ratnapura or City of Gems in Sri Lanka is famous for its sapphire and ruby mining along with some other precious stones. Amethysts are mined all over the world but those with the highest saturation are mined in Australia. Emeralds are mostly found in mines of Mexico while Brazil is the largest source of sapphires. Russia is famous for alexandrite deposits. In the underdeveloped world, gemstones are still mined by small scale miners using rudimentary tools, fire and homemade explosives.

Gems form in the earth’s crust when the molten rock below it rushes through the crevices formed in the area where lava meets the lower most layer of earth’s crust. Once the super hot lava starts cooling down it starts to crystallize. Sometimes when the process of cooling is fast, instead of crystal a non-crystalline stone is formed after solidification. The type of stone that eventually forms depends upon the type and saturation of various minerals in the cooling lava. Rubies, for example, are formed from corundum or aluminum oxide.

Most gems are mined after a tedious search process but in rare cases landslides cause a precious rock to be laid bare. One of such reported incidents include the accidental discovery of sapphire in Kashmir in 1880 where foot long rocks of sapphire were discovered by a hunter.

Gemstones that are mined are in a rough form and only experts can sift gemstones from worthless rock. Production of high quality rough gemstones is in short supply and there is a huge demand for them. In fact, acquiring rough gemstones is one of the most challenging jobs in the gemstone industry.

Rough stones have to cut and polished and this stage makes all the difference between making a profit and losing money. Skilled workers and precision cutting machines are used to give them the appearance of sparkling gems. Heat can improve the color and clarity of a gemstone. For example, citrine is made from heating amethyst. Tanzanite is almost always heated to remove brown undertones and to give it a sparkling blue or purple color.

Some gemstones are used in the natural form: crystal or non-crystal. Most gem stones are however cut and polished before they are sold to stores or jewelry manufacturers. Here again there are two ways that gems are cut and polished. Opaque stones like opal gemstone and turquoise are cut as cabochons- highly polished and cut convexly but without facets. These are fashioned to reveal the precious stones’ color and surface properties. Transparent gems are usually faceted, which is cutting with a faceting machine by polishing small flat windows at regular intervals and exact angles.

The color is the most fascinating and attractive feature of a gemstone. Cut and polish is instrumental in bringing out the best in gemstone. Daylight or white light is actually a mixture of different colors. When it passes through a substance, some of the colors are absorbed and others pass through. The unabsorbed color is what we see, which is white light minus the absorbed colors. The same material can reflect different colors despite being made from the same constituents. For example, ruby and sapphire are both made from aluminum oxide but exhibit different colors.

The story of gemstones does not stop here. These are then placed in metal to make jewelry like pendants, rings etc. The job was initially done by artisans using hand tools. The job has partially been taken over by sophisticated machines for mass production. Some extremely intricate designs are still made by hand and valued much more than machine made jewellery.

By: Mithun Rao

About the Author:




Mithun Rao, a jewelry professional, holds degree in gemology and jewelry design from Mumbai and has spent 10 years in the industry (including running his own jewelry shop). To know more about gemstones please visit gehnabazaar.com which has more than 30 precious gemstones information



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Clear as spring water from the Himalayas, the rock crystal, Sphatikam in Sanskrit, is probably one of the most auspicious crystals to be found on Mother Earth. It isn’t necessarily the easiest task to describe its attributes with words. The simple, colorless, glass transparent and cool to touch stone has fascinated the human eye for over a 1,000 years and will continue to do so through posterity.

Being simple silica in composition, SiO2, by far, is the single most composition, found in abundance on the Planet. All though all the silica need not be from Rock Crystal only, it could also be the secondary deposit of Siliceous nature.

Occurring in Hexagonal Habit with a sharp termination some times Both Ends, the Rock crystal is the Humblest of all crystals, however the reverence it commands is legendary. The magnitude of its meta physical properties is acknowledged by Modern Science, Occult, Spiritual and Yogic sciences. Reiki masters would be helpless with out its existence. The use of Crystal lenses, mirrors, Prisms, Pyramids, Wand, etc needs no special mention as it is due to its wholesale appeal to “Energy Specialist” and Gurus.

Single Termination (Point), Double termination (Double Point) and Twin Crystals are the most sought after Specimens in the kingdom of crystals.

The heavy String of 108 Beads have adorned some of the ultimate Seers ever to tread on this planet. The cool (sheetal) caress of Rock crystal Beads (6-20 mm) on the skin even during summers defy all logic known to man. The absence of Crystal cleavage lines makes the crystal strong and although brittle to impact, lends it the compact and apparently unbreakable endurance.

Collectors attempt to get Rock crystal carvings and Trinkets.The Rutilated Quartz Items are a rage.Some Smokey Quartz are being reported to occur with Cognate water trapped in the structure.

Special applications like,crystal ball,energy wand, and Lenses are much in demand. Scientifically the Rock crystal wedges make great oscillators.The crystal was also used to make electronic wrist/clock watches called quartz watches.

High temperature Crystals call Trydimite and Christobalite are used in Sophisticated Scientific Research to this day.

Rock crystal occurs in many places on the face of the earth, African Countries, Europe, U.S, Brazil, Madagascar, India (Himalayas) to name a few.A quick visit to the local museum would present,in most,would throw up a grand opportunity to see and cherish the various applications,in which the Rock Crystal has been used.From Fine carved Wine Glasses to beautiful Jewelery Boxes,and gold inlay-ed objects of Beauty.It is rare to see a Pink/Rose colored Rock Crystal,single or double terminated,however they are not impossible.As for Golden Rutilated and Tremolitic Rock crystal are a rage.

With its Mohs scale of hardness being 7,it is fairly easy to grind/cut as compared to say Rubies or Diamond for that matter. It lends itself to excellent Tumbled stones or Polishing techniques. All though most of the crystals being Medium sized, large 80-120 Kg Pieces are not so uncommon. I have had the opportunity to see and Touch a 60 Kg Rock crystal, Mayru Sriyantram.The cutter Lacchuram Verma of Jaipur took all of 3 Months to carve and polish this giant Mayru and the price! Priceless.

By: Pradeep Gour

About the Author:




I am an ardent Gem cutter and also the Head of the department of Gems and Jewellery Department at Queen’s school of design, Mysore, Karnataka, India.



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Ultra hard materials are the result of modern research and development. The last century witnessed extra ordinary growth in many fields of science and technology including material science. The latest developments in science and technology resulted in the use of very hard materials in mechanical, automobile and aviation fields. This in turn resulted in the development of new ultra hard cutting materials to machine these parts. Beside carbide cutting tools several other ultra hard materials like ceramic, polycrystalline diamond (PCD), monocrystalline diamond (MCD-natural diamond), diamond coatings on cutting tools, synthetic monocrystalline diamonds as well as polycrystalline cubic boron nitrite are developed.

Polycrystalline Diamond (PCD)
Polycrystalline diamond plates are manufactured by high temperature and high pressure process where the diamond coating is directly combined with a carbide support. Polycrystalline diamond is made by sintering of high quality diamond powder with metallic binder. Depending upon the application polycrystalline diamond materials are available in various grain sizes. For example the diamond with rough grain sizes are used for making cutting tools with excellent wear resistance due to its ability to retain cutting edge for a longer period. Incase you need very high surface finish on machines parts, then ultra micro grain sizes are highly preferred. Medium grain sizes are used for general all purpose cutting tools since it is a balance between high wear resistance of rough grain size and superior finish of ultra micro grains. This makes the medium grain sized polycrystalline diamond as an excellent ultra hard material for manufacturing high quality metal cutting tools.

Natural Diamonds
Mono crystalline diamond (MKD) is natural diamond out of pure carbon. These natural diamonds enable the production of geometric defined flutes with absolutely notch free flutes. Natural diamond (MKD) is on of the ultra hard materials which is suitable for achieving very high surface finishes for mirror bright surfaces, machining of non-ferrous materials, micro machining and machining of titanium without burr.

Synthetic Monocrystalline Diamond
Further research and development resulted in synthetic mono crystalline diamonds which are available in triangles and rectangles with an edge length of approximately 8mm. The natural diamonds often contains nitrogen and the it could have varying hardness and thermal conductivity. Whereas the synthetic monocrystalline diamonds have uniform structure with constant thermal conductivity and less internal stress. Today synthetic monocrystalline diamonds are being produced in various shapes and sizes which offers great application possibilities of this ultra hard material in future. Researches have found considerable improvements in synthetic monocrystalline tool life, improved surface finish and constant wear behavior compared to other ultra hard materials like PCD and natural diamond.

Diamond Film Coating (CVD Process)
Diamond film coatings are done to improve the surface hardness of cutting tools. Generally diamond film coatings can be classified into two. The thin diamond film coating with a layer thickness of approximately 5-20 microns and thick diamond film coating with a layer thickness of approximately 0.5mm. Higher thermal and chemical stability and ultra surface hardness are the advantages of diamond film coating. Low fracture toughness is the disadvantage of of diamond film coatings. And compared to polycrystalline diamonds no binder is used while producing diamond film coatings which causes higher splintery fracture.
Diamond film coated ultra hard materials are best suitable for machining of aluminium alloys with high silicium contents as well as graphite and carbon. Tests show very good use of diamond coated tools in machining plastics, gold alloys and wood machining.

Polycrystalline Cubic Born Nitrite (CBN)
Polycrystalline Cubic Born Nitrite is the hardest cutting material after ultra hard materials like ceramics and diamond. CNB is manufactured by a sinter process of high temperature and pressure using selected particles of Cubic Born Nitrite. Depending on various cutting applications polycrystalline cubic born nitrite are available with with different binder phases as well as in fine, medium and rough grain structure. CNB is an ultra hard material with excellent thermal stability up to 1200

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