What is gcal

Subscribe to the diamond and gemstone 'blue book' pricing guide for wholesale and auction markets. Stunning videos record the sparkle and beauty of your diamonds and gemstones. Hi-res photographs of the crown and pavilion record a diamond's true beauty. None of which come close to the professionalism and courtesy, shown towards us the way only GCAL can.

Once we point out your guarantee against what the bigger labs do, there are no more questions about your lab, you put your money where they can see it in writing. Please keep up the good work, you will continue to get our business". The most professional and accurate lab I have worked with in my 30 years of being in the industry".

Their verification process should be an industry standard. This is an essential consumer protection program". Learn about the 4C's. Why you need a GCAL certificate. Confirm your jewelry meets FTC standards for precious metal content and is free of toxic metals. Protect your investment with the most advanced diamond fingerprinting and tracking technology.

Evaluate fine jewelry assets for estate, fair market, liquidation, collateral and legal matters. A set of Master fluorescent diamonds is used to compare the strength of fluorescence.

This intrinsic property is a permanent identifying characteristic of your diamond. Clarity is graded by examining your diamond under a microscope to assess internal and external characteristics such as crystals and feathers. A gemologist first inspects the diamond in the face-up position to find obvious inclusions.

To find minute inclusions, the diamond has to be viewed through the pavilion as it is slowly rotated at least 3 full times, changing the viewing angle each time. The gemologist must assess the number, size, type, position and relief of each inclusion. After thorough inspection under the microscope, a 10x loupe is used to view the diamond in 4 different positions to determine the final clarity grade.

Before grading, every diamond is tested to confirm its origin - either natural earth mined or lab grown. If a diamond's origin cannot be verified by the initial spectroscopic analysis, then it is sent to the research department where additional more advanced tests are used to determine its authenticity. Considerable investment in state-of-the-art technologies has made GCAL one of the most well-equipped gem labs in the world.

Once your diamond's origin is determined, it is ready for grading. Photomicrographs are taken of the crown and pavilion of your diamond. These photos provide a forensic record of the exact appearance and condition of your diamond, and show internal and external characteristics visible at 10x magnification. Photographs are the most accurate way to illustrate the exact appearance and location of inclusions. Through these viewers, it is possible to assess the alignment and consistency of every facet by looking at the equality of light return, or the hearts and arrows patterns.

A precisely faceted round brilliant diamond exhibits a pattern of eight arrows through the crown top side, and a pattern of eight hearts through the pavilion bottom side. GCAL is the only laboratory that takes a real photograph of each diamond in the specialized viewer. The Optical Brilliance image is actually a digital photograph of the diamond taken in a special lighting environment that creates a strong contrast between the bright and dark areas.

The image is then processed in a proprietary computer program that calculates the percentage of brilliance and the amount of light loss. This is a scientifically accurate and repeatable way to measure brilliance. The light gray areas of the image are facet outlines resulting from image processing to provide a realistic representation of the diamond's unique faceting.

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