Colorful gemstones are just anybody’s dream to have. Their natural colors more than match your very fashionable dresses. Their sheer range could strike you spell bound. Gemstones are precious or semiprecious mineral stones which when cut and faceted can be used as jewels.
There is more to gemstones than just being jewelry items. They are regarded as lucky when worn specific to an individual’s birth month. Before we deal with this aspect in detail lets see the classification of gemstones.
Classification and Characteristics of Gemstones
There is a tri-level classification of gemstones namely, groups, species and varieties. Simply put, rubies which are red in color belong to conundrum species which in turn belong to hematite group. Others like emerald, aquamarine, goshenite, heliodor and morganite, all of them belong to that variety known as beryl. There are over 150 different species available.
Gemstones display all characteristics of crystals like dispersion, refractive indices, hardness, and specific gravity etc. They also possess characters like inclusions, fractures and cleavage which play upon their quality and values. However gemologists include all gems into the precious list.
Hardness is another important characteristic of gemstones. Simply put, hardness means resistance to scratch which is measured in Mohs, a system developed by an Austrian mineralogist F. Mohs. The scale of hardness reads from 1-10 with higher number indicating the hardest. If talc is at the bottom with just 1Moh, diamond has 10Mohs. Other popular gemstones like feldspar, topaz and sapphire having Mohs of 6, 8 and 9 respectively.
Birth Stones
US Geological Survey lists gemstones classified as birth stones. It is believed by most people that wearing birthstones brings luck to their lives. It is not surprising that all societies have this kind of faith with regards to gemstones, albeit with differences here and there, looking at the romancing tryst every society had with these ‘stones’. The list is in the order of calendar months with each month having at least one gemstone specific to that month. One can find a list of birth stones on official website of USGS.
Buying Gemstones
USGS cautions buyers against unscrupulous sellers as more and more of them are trying to push through synthetic gemstones as genuine pieces to unsuspecting, inexperienced buyers. Gemstones are measured by size and carats. (1carat=1/5th of a gram.)
When buying gemstones, watch out for:
1.Heating alters the color sometimes improving clarity
2.Irradiation darkens colors
3.Impregnation with wax, resins etc fills cracks, flaws
4.Fractures filled by injecting plastic
5.Differential colors in center and surface indicates diffusion treatment
Always buy from reputed sellers who produce certificates by Gemological Institute of America to prevent a lucky stone turn unlucky.
Alan Ross is a regular article contributor on many topics. Be sure to visit his other websites Gemstones and Diamonds |
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