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 Amethyst 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.