Jewelry Appraisal and Repair Houston

Gemological Processes

IDENTIFICATION | CLASSIFICATION

GEMSTONE IDENTIFICATION

Before a gemstone can be graded for quality, it must be examined and identified. This is Gemstone Identification.

In this process, the gemologist will review the obvious characteristics of the gemstone. The microscope is then used to gather further information. Additional tools and instruments are needed in testing until the gemstone has been identified. The objective is to obtain the most amount of evidence possible.

With the presence of synthetics (lab grown) and simulants (imitations) in the market, gemstones can be quite challenging to identify; even with the right tools. Knowing whether or not your gemstone is completely natural, treated, lab-grown, or simulated is vital to any investment.

Blue Sapphire; Gemstone General Observation

General Observation | Species & Variety

Microscope | Photomicroscopy

Gemstone Treatments | Synthetics & Simulants

$Refractometer Gemological Instrument$

Further Testing & Gemological Instruments

“ Like the physician, the architect and the engineer, the gemologist must complete prescribed studies and examinations in order [to be] of exceptional service to the public [in] the profession of Gemology. ”

- Robert M Shipley

FATHER AND FOUNDER OF GIA

DIAMOND GRADING

Diamonds are systematically divided into precise grades using the GIAs Four Cs.

Carat (Weight) | Diamond Color | Diamond Clarity | Diamond Cut & Finish:

What's it Worth?

Because so much is spent on diamond mining, these gemstones are examined from every angle and characteristic. GIA created this diamond grading system. When graded properly, it is fairly easy to determine a natural diamond's appraised value through the GemGuide or Rapaport.

Gemworld International researches both, the global and U.S. gemstone market. They release new market pricing consistently through the GemGuide. Rapaport is listed as "NEW YORK HIGH CASH ASKING PRICES" in fine print. Dealers commonly use Rapaport.

Gemworld International is more a credible source for wholesale pricing and investments. It is the actual researched wholesale asking price from U.S. sellers for gems. In addition, they work in closely with GIA to serve the industry.

Below are the Four Cs of Natural Diamond

Diamond Carat Weight & Sizes

Colorless to Fancy Color Diamond Grading

Diamond Clarity Grading

Diamond Cut Grading | Fancy Shaped

COLORED STONE GRADING & CLASSIFICATION

Like Diamonds, Colored Gemstones are also weighed and sold in carats. Information on Carat Weight is above in the Diamond Section. Because of the similarity, we have chosen to hi-light Gemstone Origin instead.

GIA describes a Gemstone's Color on a 31 Hue Color Wheel. Body Color, Tone, and Saturation are the three elements that define a gem's color. These three elements convey thousands of color combinations. It allows us to convey a stone's color more precisely. This procedure is very different from color grading diamond.

Furthermore, you should not describe the stone's Clarity Grade as VVS, VS, SI, etc. That is categorizing the colored stone on the Diamond Clarity Grading Scale. Similar to grading Color, GIAs Colored Stone Clarity Grading System is also separate from Diamond. When clarity grading for colored stones, gemstone formation and the gem's Color are taken into account.

Cut is described and graded differently as well. Some stones are cut into calibrated, ready to set, sizes.

Ultimately, without being able to identify and accurately grade a Colored Gemstone, its intrinsic value cannot be determined.

Below are the Colored Gemstone identification and grading attributes