Many laboratories these days provide a diamond sealing service after the diamond is tested.
A sealed diamond report by the International Gemological Institute (IGI).
Usually upon request the stone is sealed together with a reduced copy of the diamond report. This assures the consumers, diamond dealers, jewelers and other professionals in the industry that the stone corresponds to the one in the report.
A sealed gemstone report by the IGI, Measurements: 76mm x 40mm (3in x 1,6in)
This report comes with rounded corners, measuring 86mm x 54mm (3,4in x 2,2in). Some laboratories make their Card Reports more resistant to wear and tear.
A diamond report in credit card format by GCAL (Gem Certificate and Assurance Lab).
Diamond report in credit card format by the IGI (International Gemological Institute).
This is slightly larger than a credit card, measuring 100mm x 70mm (3,9in x 2,8in).
Logo of GCAL
GCAL provides some of the most advanced diamond reports in the industry.
According to their website GCAL is the only laboratory that provides 100% guaranteed diamond grading certificates.
Their website also states thet GCAL is the only diamond grading laboratory that:
i) Provides a â€œZero Toleranceâ€ 4C's Consumer Grading Guarantee
ii) includes Gemprint® Security Registration with every certificate
iii) is ISO 17025 accredited in North America
iv) Measures, examines, weighs, analyzes, tests and photographs every diamond several times.
v) includes Diamond Profile® light performance analysis
The GCAL guarantee states that you can challenge a GCAL certificate within two years of the date of application if it does not meet the quality grades or carat weight stated on the certificate. The certificate and diamond will be reviewed by GCAL directors. If it is determined by GCAL that either the weight or quality grade is lower than the weight or quality grade originally assigned on the applicable certificate, or the diamond is not authentic, GCAL will, at your option, either:
a) Reimburse you the difference between the current fair retail value of your diamond at the original grade or weight, as may be applicable, and the current fair retail value of your diamond at the newly established grade or weight, as may be applicable, or
b) Replace your diamond with an authentic, natural with weight and quality grade as stated in the original certificate of the diamond.
The guaranteed certicicates issued by GCAL includes:
i) Diamond ID
ii) Cut Grade
iii) Hearts and Arrows
iv) Diamond Audit
v) Light performance
vi) Gemfacts Digital Certificates
The Front Cover of the GCAL Diamond ID Certificate
The Back Cover of the GCAL Diamond ID Certificate
The Inside Panel of the GCAL Diamond ID Certificate
The GCAL Diamond ID Certificate when open- See details below
Some of the unique features of a GCAL report are:
i) Photomicrograph of the diamond with magnification up to 10X - From the top and bottom of the diamond.
ii) Actual photograph of the laser inscription. This is a close up shot of the laser inscription taken at up to 50X magnification.
iii) A unique optical fingerprint for each diamond tested, patented by GCAL called Gemprint.
iv) Optical brilliance analysis. This is done under controlled lighting environment. Captured and calibrated at different viewing angles. This test shows the amount of light returning from the diamond. Areas of light leakage are shown dark blue shades.
v) Optical symmetric analysis. By analyzing the light exiting the diamond, this test shows the discrepansies in the balance of the diamond. A symmetrical patern shows that the light is well balanced and therefor of exceptional quality.
In addition this test gives a visual representation of proportions and facet alingment.
Sample of a Light Performance Diamond Certificate by GCAL- Details see below
Dr Shihaan Larif
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