Natural gemstones are delivered to us courtesy of nature, with no interference from humans. By the time they appear in our jewelry they've been cut or polished, but they've not been altered in other ways.
A genuine gemstones is the real thing, but isn't natural anymore if it was treated in some way to enhance its appearance.
Enhancements allow jewelry manufacturers to improve the look of gemstones that consumers wouldn't otherwise purchase. Treated gemstones are genuine, but they are no longer considered natural. If naturally "perfect" stones were the only ones available, most of us could n't afford them.
A synthetic gemstone shares a natural stone's physical, chemical and optical qualities, but it is created in a laboratory. It's kind of like making a high tech batch of cookies -- we know the ingredients and we know how long to cook them. There are synthetic versions of nearly all popular gemstones and many versions have been available for a long time. Older synthetics were fairly simple for gemologists to detect, because they were often too perfect. Some modern synthetic gemstones look more natural and are more difficult to identify, but an experienced jeweler or gemologist can usually classify them.
Jewelry that includes quality synthetic gems can be just as beautiful as jewelry made with natural stones. Good synthetics aren't always inexpensive, but should cost much less than natural stones of similar quality.
Since synthetic gemstones have the same composition as their natural counterparts, they could technically be called genuine, but that would be considered deceptive labeling if the stone's origins are not disclosed. Question the ethics of anyone who knowingly omits origin information, and the expertise of anyone who cannot provide it.
, Many people decide to go with jewelry that combines several birth stones into one item, a birthstone bracelet, for example. Others prefer single stones. The birthstone chart, below, will take you to either an article or a merchant site where you can get more information on that particular birth stone.
| Birth Month | Modern Birthstones | Traditional Birthstones | Mystical Birthstones | Ayurvedic Birthstones | Other Birthstones |
|---|---|---|---|---|---|
Garnet | Garnet | ||||
Amethyst | Bloodstone | Amethyst | |||
Bloodstone | |||||
Diamond | Quartz, White Sapphire | ||||
Emerald | Sapphire | Chrysoprase, Beryl | |||
Alexandrite | Moonstone | Opal | |||
Ruby | Ruby | Ruby | Carnelian | ||
Sapphire | Jade | ||||
Sapphire | Agate | Moonstone | Lapis Lazuli, Diamond, Chrsolite | ||
Tourmaline | Opal | Pink Tourmaline, Zircon, Aquamarine | |||
Citrine | Topaz | Diamond | |||
Zircon, Turquoise,Lapis Lazuli | Ruby |
|
, 
Day Of Birth Gemstones:
| If you were born on: | Your Day-Of-Birth Gemstone Is: |
| Sunday | Topaz |
| Monday | Pearl |
| Tuesday | Garnet |
| Wednesday | Amethyst or Cat's Eye |
| Thursday | Emerald (Similar color gem in semi-precious is Peridot) |
| Friday | Topaz (See Blue Topaz, Smoky Topaz) |
| Saturday | Sapphire (Similar color semi-precious: Iolite) |
#1 is softest..................#10 is hardest
| #1 | Talc |
| #2 | Gypsum |
| #3 | Calcite |
| #4 | Flourite |
| #5 | Apatite |
| #6 | Feldspar |
| #7 | Quartz |
| #8 | Topaz |
| #9 | Corundum |
| #10 | Diamond |
Gemstones and Mohs Scale
Diamond:....................10
Syth. Moissanite:........9.5
Corundum:..................9
Cubic Zirconia:............8.5
Spinel:........................8
Topaz:........................8
Emerald:.....................7.5 - 8
Almandite:...................7.5
Rhodolite:....................7 - 7.5
Pyrope:.......................7 - 7.5
Spessartite:.................7 - 7.5
Tourmaline:..................7 - 7.5
Iolite:...........................7 - 7.5
Quartz Group: .............7
Peridot:.......................6.5 - 7
Jadeite:.......................6.5 - 7
Andradite:....................6.5 - 7
Scapolite:....................6.5
Zircon (low):.................6.5
Tanzanite:...................6.5 - 7
Feldspars:...................6 - 7
Nephrite:.....................6 - 6.5
Opal:..........................5.5
Lazulite:.....................5 - 6
Lapiz Lazuli:...............5- 6
Turquoise:..................5 - 6
Stainless Steel...........5.5
Sphene:.....................5 - 5.5
Apatite:......................5
Rhodochrosite:...........4
Coral:........................3 - 4
Refractive index, or RI as it is often abbreviated, is one of the most important signatures of a gemstone. Measuring refractive index is one of the first steps in identifying a gemstone, though some gemstones have similar refractive indices and additional tests are required for a definitive identification.
RI is the ratio of the velocity of light in air to the velocity of light through a transparent material. If light passes from air into a transparent material at an angle of incidence other than a 90 degree angle, it is deflected at a different angle (the coincident angle) according to the RI. Gemstones with higher RI are generally more brilliant than those with low RI, because more light is returned back out the top or crown of the stone, instead of passing through the bottom or pavilion. Diamond has an RI of about 2.4; quartz, about 1.54-1.55. The RI of most gemstones is easily measured using a simple optical instrument known as a refractometer.
Some gemstones are singly refractive: they have only one refractive index. Other gemstones -- in fact, most -- are doubly refractive: they have two different refractive indices. When a beam of light enters a doubly refractive gem, it is split into two beams, each travelling at a different speed and on a different path through the crystal. Birefringence is a measurement of the difference between the two refractive indices in gems that are doubly refractive, and it ranges from a low of .003 to a high of .287. Very few gemstones are singly refractive; in fact, the only well-known gems with that property are diamond, spinel and garnet.
The following chart lists the refractive indices for 126 varieties of gemstones, sorted in descending order.
Refractive Index of Metals
Platinum: 2.330
Titanium: 2.160
Copper: 1.100
Nickel: 1.080
Gold: 0.470
Silver: 0.180
Gems Classfication
Gemstones in the Oxides class:
Variety: RUBY
Variety: SAPPHIRE
Variety: ALEXANDRITE
Variety: YELLOW-GREEN CHRYSOBERYL
Variety: CAT'S EYE CHRYSOBERYL
Gemstones in the Carbonate class:
- AZURITE (often in combination with malachite)
- MALACHITE
- RHODOCHROSITE (both massive and crystalline)
- SINHALITE (a borate mineral)
Gemstones in the Phosphate class:
Gemstones in the Silicate class:
Variety: AQUAMARINE
Variety: EMERALD
Variety: GOSHENITE
Variety: HELIODOR
Variety: MORGANITE
Variety: RED BERYL
Variety: IOLITE
Variety: DEMANTOID
Variety: HESSONITE
Variety: TSAVORITE
- JADE (a variety of two minerals: Jadeite and Nephrite)
- KORNERUPINE
- OLIVINE
Variety: PERIDOT
Variety: AMETHYST (violet)
Variety: CITRINE (yellow to orange)
Variety: PRASIOLITE (green)
Variety: ROCK CRYSTAL (colorless)
Variety: ROSE QUARTZ (pink)
Variety: SMOKY QUARTZ (gray to black)
Variety: LARIMAR
Variety: KUNZITE
Variety: HIDDENITE
- TITANITE (also known as sphene)
- TOPAZ
- THE TOURMALINES:
Variety: INDICOLITE
Variety: TANZANITE
Gemstones in the Mineraloids class:
Variety: MOLDAVITE
Precious Metals (in the Elements class):
Planets and their Gem Stones
In Astrological works, the nine planets have been assigned nine different gemstones. According to the classical famous astrological work 'Jatak Parijat' we can divide the planets and their stones as follows:
| Planet | Gem Stone |
| Sun (Surya) | |
| Moon (Chandra) | |
| Mars (Mangal) | |
| Mercury (Budha) | |
| Jupiter (Guru) | |
| Venus (Shukra) | |
| Saturn (Shani) | |
| Rahu | |
| Ketu |
Telugu to English translation of Gem Stones
Kempu(Maanikyam) - Ruby
Pacha(Marakatham) - Emerald
Pushyaragam - Yellow Sapphire
Gomedhikam – (Yellow)Zircon
Neelam(Indraneelam) - Blue Sapphire
Vajram - Diamond
Vaiduryam – cymophane/chrysoberyl (Cat's eye)
Muthyam -
Pagadam – Red Coral
