Gemstone Buying Tips

Hi All

I see that lot of us have questions on gemstone buying and how to questions..so thought of posting some info which I have gathered by researching. most of the simple ones we can follow before buying the gems....hope this helps...


Gemstone Buying Tips

• Gemstone jewelry is beautiful and if well cared for can last centuries. Here are some ways to get the best gemstone jewelry for your money.
  Gemstone Jewelry Pricing
  
  
  Gemstone price is determined by: size, cut, quality (color/clarity/treatments), and type. Here are some questions to ask about gemstone quality:
  • Questions on Gemstone Size
    • How big is the actual gemstone?
    • Will the gemstone be too big or too small for the intended setting?
  • Questions on a Gems Cut
    • What type of gemstone cut? A well dimensioned "Brilliant" cut sparkles the most.
    • How regular is the gemstones cut?
    • What are the dimensions of a cut? The deeper (total depth) the gems cut, the more it will sparkle.
  • Questions on Gems Overall Quality
    • Are the gems damaged? Are there noticable chips, inclusions, or marks?
    • Has the gemstone been treated? (See treatments listed below)
    • Is the gem natural or synthetic?
  • Questions on Gemstone Color
    • Is the gemstones color even?
    • How good is the gems color? (Is it vibrant?)
    • If you are buying the gemstones for earrings or cufflinks, are the gem stones well matched?
  Gemstone Treatments
  
  
  Jewelry dealers may treat gemstones in hopes of gettng a higer price. The savvy buyer asks lots of questions and hopefully tests the results. Here are some gemstone treatments to look for:
  • Coatings: Jasper is often dipped in petroleum products to bring out color and to seal it. Emerald is oiled; turquoise is waxed.
  • Dye: This is the most common treatment used. On clear gemstones, dye may be visible in cracks that are darker than the rest of the stone. Sometimes dye appears as a residue that rubs off or white patches. Lapis and Rose Quartz are commonly dyed. Amethyst and Citrine are often dyed. Black Onyx is permanently dyed in normal processing.
  • Fake Gem Stones: Some dealers will try passing off fake gems instead of natural ones. There are fake stones for most gemstones on the market. Always ask what gemstone something is if you are not certain. Honest dealers will tell you. If a gemstone looks too perfect it may be fake, irradiated or dyed. I avoid laboratory made products also known as synthetics (unless getting a really good discount).
  • Gemstone Swap: When a deal seems too good to be true, the dealer may be substitutiong one gemstone for another. For example, dyed Howlite is often substituted for Lavendar Jade.
  • Heat Treatment: Amethyst, Aquamarine, Ruby, Tanzanite and Topaz are often heated at high temperatures to enhance color.
  • Irradiation: It is common to irradiate Aquamarine, London Blue Topaz, Emerald, and Diamond as well as other gem stones. This treatment brings out color and removes imperfections. Many dealers know if the gemstones they are selling have been irradiated. Honest ones will tell you if they are aware of the treatment.
  Tips on buying gemstone beads
  
  • Look for the best quality gemstone (if buying real gemstones)
  • Verify that the cracks in a gemstone bead are not darker than the bead itself (if so, the bead is dyed)
  • If the beads are being sold in a 16" strand -- I make sure it is 16" -- not 14" or 15" if possible.
  • Make sure beads are not cracked or chipped by the holes as this tears the thread
  • Evenly shaped beads (as appropriate)
  • Good color (so can create harmonious necklaces and matching earrings)
  • Good sized holes (so can use a stronger thread)

Gem Stone Identification
Steps to Identify Gem Stones!
So, you have a pretty stone, and you want to know just what it is you have! Maybe it's a diamond gem stone, or an emerald gem stone, or maybe it's a close cousin, or even a piece of colored glass. That's where the science, (and art) of gem stone identification comes in.
If you are confused about the identity of your gem stone, don't feel embarrassed. Kings and emperors have made the same kind of mistakes in identifying gem stones themselves.
Take the ruby. It's a deep red crystal, very hard and very beautiful. And very hard to distinguish from its mineralogical cousin, the very beautiful but somewhat less rare spinel.
Chemically very similar, containing only one extra ingredient in its molecular mix, those who would be experts at identification of gem stones have often mistaken the spinel for the ruby. The most famous case of mistaken identity is the Black Prince Ruby, actually a 170 carat spinel, which has been for centuries a part of the Crown Jewels of England.
So, how does one go about identifying gem stones? Well, it takes some training, some special tools, and a lot of patience.
Identifying Gem Stones – Step 1:

First, try to make sure that, the gemstone that you have, is a gem stone. Some times what you think may be a gem stone is just a pretty rock or a piece of metallic ore.
Since the term gem stone is largely arbitrary, this can be hard. Some basic guidelines include:

• If it's rough and sandy, it should not be identified as a gem stone, no matter how pretty it may be.
• If it's malleable, that is easily able to be shaped by hammering, crushing or bending; it is probably a metallic ore. Gem stones are primarily identified by a crystalline structure, which can be shaped, but not easily shaped and then only by cutting, fracturing or abrasion.
• A pearl, though used in jewelry, is not considered a gem stone. (Though if you want to identify it as a gem stone, go ahead. I won't tell anyone.)
• It is tempting to identify fossilized wood as a gem stone because of its shiny, lustrous surface and its attractive lines and colors, but it is not considered a gem.

Identifying Gem Stones – Step 2:
Hardness:
In the identification of gem stones, hardness is one of the most important of all tests. While not usually a definitive way to identify a gem stone, it does at least put you into the correct group of possibilities.
To help you use hardness to identify a gem stone, there are a variety of hardness scales that you can use. The most common is the 'Mohs' Scale' which ranks mineral hardness on a scale of one (talc) to ten (diamond).
To measure the hardness of the gem stone you wish to identify, you will use a hardness kit. This contains a set of substances of varying hardness keyed to one of the hardness scales.
If your test substance can scratch the subject gem stone, then the test substance is harder than the subject gem stone. By trying several test substances on your subject gem stone, you will be able to approximate the hardness of the subject.
Since diamond is often too expensive for most kits, glass is sometimes used in its place.
Identifying Gem Stones – Step 3:
Cleavage:
This refers to the tendency of crystals to break along fixed planes in their structure. By striking the crystalline gem stone, you can examine the break and compare it to various cleavage charts.
Many gem stones, including quartz and mica, are easily identified by this way. If you suspect that your gem stone is extremely valuable, like a diamond, you may want to skip this step.
Identifying Gem Stones – Step 4:
Streak:
This is a method of gem stone identification that involves using the subject gem stone to make a mark on a hard, ceramic plate. Many (but not all) gem stones will leave a streak. By comparing the appearance of this streak to various charts, you have another clue to use in gem stone identification.
Identifying Gem Stones – Step 5:
Crystal morphology, or shape.
Most gem stones are made up of crystals, each with a unique shape based on their atomic and molecular structure. A simple example of crystal shape can be seen by examining sugar crystals and salt crystals under a powerful glass. While they may look the same in a bowl, up close their crystal shapes are very different and unique.
Identifying Gem Stones – Step 6:
Color:
While this may seem the first test to use when classifying a gem stone, using color to identify a stone is not as reliable as you might think.
Most people view the sapphire as blue, but this cousin to the ruby can be found in various shades including pink, green, yellow and almost transparent. The classic diamond, with its colorless crystal, looks so much like the less rare cubic zirconium or cubic zirconia, that they almost indistinguishable without a close examination.
Identifying Gem Stones – Step 7:
Chemical and Physical tests:
These methods of identification of gems most often used by experts because they usually require special equipments. The tests include:

• Specific gravity.
• Refractive Index.
• Light Dispersion.
• Color changes.

Once you have your list of measurements, and a reliable set of tables for comparison, you are well on your way to identification of your gem stone.
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Thanks ManuuRaghuu..I am not really that much of an expert..however if you are planning to buy ensuer that you are buying from an authenticated store rather than a regular jewellery store.for diamonds atleast we get a certificate..but for other gem stones i dont think they give certificate in India..neither in US...but yes if you are in US..here you can try to buy a ruby ring directly from a good american store..as we all know they will give us all the details even the weight of the gem stone and the gold carat etc..