Gem Stone
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 Blue Goldstone Crystal Gemstone Chip Bead Bracelet Healing  US $7.11
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 AMETHYST 52 MM GEM STONE CRYSTAL BALL CRYSTAL SPHERE US $9.38
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 Healing Set Beautiful Natural Crystal Amethyst Gemstone Obelisk Point Sphere Bal US $19.99
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 CHATOYANT TIGERS EYE GEM STONE 45 MM CRYSTAL BALL CRYSTAL SPHERE US $26.56
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 OOAK Old World Medieval Natural Red River Jasper Turquoise Gemstone Pendant US $16.00
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 Large HEMATITE Worry Stone Healing Gemstone Therapy Stone Reiki Energy MY10 US $8.95
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 12 Tiger Iron Stone Sphere Stone Carving 30mm Gemstone Sphere Reiki TGI0 MY8 US $9.95
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 Large RHODONITE Worry Stone Healing Gemstone Therapy Stone Reiki Energy MY9 US $8.95
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 Large CALCITE Worry Stone Healing Gemstone Therapy Stones Reiki Energy MY12 US $8.95
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 Large UNAKITE Worry Stone Healing Gemstone Therapy Stones Reiki Energy MY13 US $8.95
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 Garnet Passion Handcrafted Garnet Gemstone Tree SCULPTU US $58.46
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 3 x DARK PURPLE AMETHYST GEM STONE MASSAGE WANDS CRYSTAL HEALING US $8.50
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 HAUNTED ITEM DREAM ORACLE AMETHYST GEMSTONE PENDANT INFORMATION OF FUTURE EVENT US $37.00
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 40mm Blue Mexican Opal Sphere Crystal Ball Gemstone US $.95
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 Obsidian Sphere Collectibles Handmade Gemstone US $.99
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 Amazing Lapis Heart pendantGemstone US $.99
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 4 Fancy Handmade White Cateye EggGemstone US $.99
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 Charming Amethyst Insert Hemming pendantGemstone US $.99
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 Obsidian Leaves pendant Beautiful Handmade gemstone US $.99
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 2 Rare Handmade Purple Cateye Healing SphereGemstone US $.99
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 580g NATURAL Septarian Dragon Crystal Gem Specimen stone US $3.99
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 GOLDEN QUARTZ GEM STONE 44 MM CRYSTAL BALL CRYSTAL SPHERE US $6.50
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 ENCHANTED BRAZIL AMETHYST GEMSTONE TREE ENHANCE SPIRITUAL CONNECTION GYPSY WITCH US $35.00
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 3 x BLUE LACE AGATE GEM STONE MASSAGE WANDS CRYSTAL HEALING US $20.50
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 116 Black Obsidian Sphere 29mm Gemstone Spheres Reiki Energy ROB MY16 US $8.95
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 12 Black Obsidian Sphere 30mm Gemstone Spheres Reiki Energy ROB MY15 US $8.95
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 2 Rare Bamboo Stone Carved Crystal Healing Gem Sphere STAND US $2.99
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 Deep Blue AZURITE CRYSTAL CLUSTER Healing Gemstone Morocco Reiki Energy AZU1 US $16.95
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 LAPIS LAZULI With Pyrite Palm Stone Gemstone Therapy Stone Reiki Energy A Grade US $28.95
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 Orange VANADINITE Crystals On BARITE Sparkly Healing Gemstone Reiki Energy VB1 US $13.95
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 2Collectibles Handmade Tigereye EggGemstone US $.99
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 Picasso Jasper Carved Crystal Skull Gemstone Healing US $.99
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 Carnelian Agate Gemstone GEM Stone Healing Dowsing Reiki Pendulum Divination US $3.99
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 Polished Carved Bamboo Stone Healing Egg Gem US $.99
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 Collectibles Handmade Imperial Taper SphereGemstone US $.99
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 29 Natural White Jade Skull Skeleton Carving 3M08healing Gemstone US $14.95
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 Polished Carved Fluorite stone Healing SphereGemS047 US $8.99
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 NATURAL amethyst quartz crystal gem stone massage wand US $7.77
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 Sugilite Carved Crystal Skull Gemstone Crystal HealingMineral US $89.95
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 Charming CARVED Mustard stone Flower PendantGem US $.99
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 New Fancy Handmade Polychrome Jasper EggGemstone US $.99
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 Polished Carved Fluorite stone Healing Egg GemS021 US $.99
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 nature PURPLE JASPER quartz crystal gem stone massage wand US $4.99
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 Carved clear quartz Crystal Gem Stone turtle healing US $3.99
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 Pretty Handmade Polychrome Jasper SphereGemstone US $.99
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 Handmade Carved Bamboo stone Healing EggGem US $.99
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 Rare Ocean Jasper Carved Crystal Skull Gemstone US $143.00
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 09 Ametrine Carved Crystal Skull QuartzGemstone US $69.95
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 Rare nature RUTILATED crystal quartz gemstone original reiki healing US $1.04
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 2 Rare nature RUTILATED crystal quartz gemstone original reiki healing US $.99
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 4pcs Rare nature black tourmalin crystal gemstone specimen reiki US $2.47
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 Charming CARVED Gold Sand Stone Flower PendantGem US $.99
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 Charming Handmade CARVED Louts Stone Healing HeartGem US $.99
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 Handmade Carved Fluorite stone Healing WandsGemW014 US $.99
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 3pcs Rare nature black tourmalin crystal gemstone specimen reiki US $1.04
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 Nice Carved Gold Sand Stone Healing SphereGemS241 US $.99
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 BIG FLASH OPAL CRYSTAL GEMSTONE BALL SPHERE CARVING US $10.95
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 Rare nature colour phantom quartz crystal gemstone reiki US $.99
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 Clear Quartz Crystal Fauceted Gemstone Pendulum US $5.99
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 Smokey Quartz Crystal Fauceted Gemstone Pendulum US $5.99
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 Rose Quartz Crystal Fauceted Gemstone Pendulum US $5.99
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 Colorful CARVED FLUORITE STONE HEALING HEARTGemS206 US $.99
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 Colorful CARVED GREEN SPOT STONE HEALING HEARTGem177 US $.99
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 Emerald Fauceted Gemstone Pendulum US $5.99
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 CHARMING CARVING FLOURITE STONE HEALING WANDSGEMW009 US $.99
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 CHARMING CARVED GREEN SPOT STONE HEALING HEARTGEM008 US $.99
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 Princess Fauceted Gemstone Pendulum 2 US $5.99
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 Polished Carved Fluorite stone Healing EggGemS055 US $.99
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 LG OCEAN BLUE Aquamarine CRYSTAL GEMSTONE SKULL CARVING US $13.95
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 Handmade Carved Bamboo stone Healing SphereGem US $.99
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 Natural Rare Crystal Gem Stone Rock Grape Malachite Blue Pendant Lucky¼healing US $9.62
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 Amethyst Fauceted Gemstone Pendulum 1 US $4.29
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 Stunning Crystal Stretch Stretch Tridacna Bracelet Gem Stone 9mm Beads¼Healing US $8.81
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 Crystal Chinese Jade Gem Stone Flower carved Extend cord Bracelet Luvky¼Healing US $9.82
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 Natural Lucky Crystal Stretch Bracelet Eye Gem Stone Tiger 9mm Bead Rock¼Healing US $8.81
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 Crystal Chinese Jade Gem Stone carved Flower cord Bracelet Extend Luvky¼Healing US $9.82
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 Stunning Energy Crystal Bracelet Black GemStone Rock Obsidian 10mm Beads¼Healing US $8.92
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 AAA Blue Shimmer Gem Stone Rock Round 9mm Lucky Crystal Health Bracelet¼Healing US $8.62
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 Energy Crystal Stretch Bracelet Black Obsidian Gem Rock 7mm Stone Beads¼Healing US $8.62
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 Natural Crystal Bracelet Color Tiger Eye Gem Rock 7mm Stone Beads Energy¼Healing US $8.61
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 Natural AGrade Amethyst Quartz crystal 5mm GemStone Necklace Rock Bead¼Healing US $9.82
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 Garnet Fauceted Gemstone Pendulum US $5.99
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 Princess Fauceted Gemstone Pendulum 1 US $5.99
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 2 pcs nature black obsidian crystal gemstone sphere ball reiki stand US $1.46
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 2 pcs nature color Aventurine crystal gemstone sphere ball reiki stand US $.99
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 2 pcs nature rose quartz crystal gemstone sphere ball reiki stand US $1.29
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 2 pcs nature yellow tiger eye crystal gemstone sphere ball reiki healing US $3.25
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 6 pcs Nature Color OCTAHEDRON FLUORITE CRYSTAL Gemstone reiki US $4.75
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 NATURAL GEMSTONE LABRADORITE PENDULUM WITH METAL CHAIN US $9.99
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 NATURAL GEMSTONE SULEIMAN PENDULUM WITH METAL CHAIN US $9.99
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 190g nature clear crystal quartz gemstone cluster point reiki healing US $4.99
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 145g nature clear crystal quartz gemstone cluster point reiki healing US $3.58
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Gem Stones
A gemstone or gem (also called a precious or semi-precious stone, or jewel) is a piece of attractive mineral, which—when cut and polished—is used to make jewelry or other adornments. However certain rocks, (such as lapis lazuli) and organic materials (such as amber or jet) are not minerals, but are still used for jewelry, and are therefore often considered to be gemstones as well. Most Gem Stones are hard, but some soft minerals are used in jewelry because of their lustre or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone. Apart from jewelry, from earliest antiquity until the 19th century engraved gems and hardstone carvings such as cups were major luxury art forms; the carvings of Carl Fabergé were the last significant works in this tradition.
For example, diamonds are made of carbon (C) and rubies of aluminium oxide (Al2O3). Next, many gems are crystals which are classified by their crystal system such as cubic or trigonal or monoclinic. Another term used is habit, the form the gem is usually found in. For example diamonds, which have a cubic crystal system, are often found as octahedrons.
Gem Stones are classified into different groups, species, and varieties. For example, ruby is the red variety of the species corundum, while any other color of corundum is considered sapphire. Emerald (green), aquamarine (blue), bixbite (red), goshenite (colorless), heliodor (yellow), and morganite (pink) are all varieties of the mineral species beryl.
Gems are characterized in terms of refractive index, dispersion, specific gravity, hardness, cleavage, fracture, and luster. They may exhibit pleochroism or double refraction. They may have luminescence and a distinctive absorption spectrum.
There are no universally accepted grading systems for any gemstone other than white (colorless) diamond. Diamonds are graded using a system developed by the Gemological Institute of America (GIA) in the early 1950s. Historically all gemstones were graded using the naked eye. The GIA system included a major innovation, the introduction of 10x magnification as the standard for grading clarity. Other gemstones are still graded using the naked eye (assuming 20/20 vision).
A mnemonic device, the "four C's" (color, cut, clarity and carat), has been introduced to help the consumer understand the factors used to grade a diamond. With modification these categories can be useful in understanding the grading of all gemstones. The four criteria carry different weight depending upon whether they are applied to colored gemstones or to colorless diamond. In diamonds, cut is the primary determinant of value followed by clarity and color. Diamonds are meant to sparkle, to break down light into its constituent rainbow colors (dispersion) chop it up into bright little pieces (scintillation) and deliver it to the eye (brilliance). In its rough crystalline form, a diamond will do none of these things, it requires proper fashioning and this is called "cut". In gemstones that have color, including colored diamonds, it is the purity and beauty of that color that is the primary determinant of quality.
Physical characteristics that make a colored stone valuable are color, clarity to a lesser extent (emeralds will always have a number of inclusions), cut, unusual optical phenomena within the stone such as color zoning, and asteria (star effects). The Greeks for example greatly valued asteria in gemstones, which were regarded as a powerful love charm, and Helen of Troy was known to have worn star-corundum.
Historically gemstones were classified into precious stones and semi-precious stones. Because such a definition can change over time and vary with culture, it has always been a difficult matter to determine what constitutes precious stones.
A few gemstones are used as gems in the crystal or other form in which they are found. Most however, are cut and polished for usage as jewelry. The picture to the left is of a rural, commercial cutting operation in Thailand. This small factory cuts thousands of carats of sapphire annually. The two main classifications are stones cut as smooth, dome shaped stones called cabochons, and stones which are cut with a faceting machine by polishing small flat windows called facets at regular intervals at exact angles.
Stones which are opaque such as opal, turquoise, variscite, etc. are commonly cut as cabochons. These gems are designed to show the stone's color or surface properties as in opal and star sapphires. Grinding wheels and polishing agents are used to grind, shape and polish the smooth dome shape of the stones.
Gems which are transparent are normally faceted, a method which shows the optical properties of the stone's interior to its best advantage by maximizing reflected light which is perceived by the viewer as sparkle. There are many commonly used shapes for faceted stones. The facets must be cut at the proper angles, which varies depending on the optical properties of the gem. If the angles are too steep or too shallow, the light will pass through and not be reflected back toward the viewer. The faceting machine is used to hold the stone onto a flat lap for cutting and polishing the flat facets.Rarely, some cutters use special curved laps to cut and polish curved facets.
Color is the most obvious and attractive feature of Gem Stones. The color of any material is due to the nature of light itself. Daylight, often called white light, is actually a mixture of different colors of light. When light passes through a material, some of the light may be absorbed, while the rest passes through. The part that is not absorbed reaches the eye as white light minus the absorbed colors. A ruby appears red because it absorbs all the other colors of white light (blue, yellow, green, etc.) except red.
The same material can exhibit different colors. For example ruby and sapphire have the same chemical composition (both are corundum) but exhibit different colors. Even the same gemstone can occur in many different colors: sapphires show different shades of blue and pink and "fancy sapphires" exhibit a whole range of other colors from yellow to orange-pink, the latter called "Padparadscha sapphire".
This difference in color is based on the atomic structure of the stone. Although the different stones formally have the same chemical composition, they are not exactly the same. Every now and then an atom is replaced by a completely different atom (and this could be as few as one in a million atoms). These so called impurities are sufficient to absorb certain colors and leave the other colors unaffected.
About the Author
I am Mohan read mathematics at Stanford and remained there for his MS. From 1998-1999 on researched in Evolution and in Animal Behavior in Camrbidge, UK. I was was then a professor in the departments of Anthropology and Biology, New Jersy College, USA. Now teaches at the department of Zoology. Carried out research in several areas of evolutionary biology, particularly in sexual selection and the comparative method.
