Diamond Certification

A diamond certificate, also known as a diamond grading report, is an easily understood document prepared by an expert gemologist that describes the key characteristics of a diamond. A certificate from a leading gemological laboratory verifies the quality of a loose diamond and allows non-experts to make educated diamond buying decisions. Buyer beware: not all certifications are created equal. Some certifications will call an I2 diamond an SI1 or a K coloured diamond an H. You should also be aware that certifications created by retailers' in-house appraisers may be inflated to create the illusion of a good deal. Below are third party certifications which I trust. 

GIA Certified Diamonds

Founded in 1931, the Gemological Institute of America (GIA) is an independent, non-profit organization widely considered as the world's foremost authority in gemology. Introduced in 1953, their diamond and gemstone grading system is recognized as an accepted standard worldwide. Gemstone manufacturers from around the globe send diamonds and gems to the GIA for expert examination and analysis.

The GIA's mission is to increase consumers' trust in diamonds and jewelry by upholding the highest standards of integrity, academics, science, and professionalism. They work toward this goal by providing jeweler and consumer education, conducting meticulous research, and developing state-of-the-art laboratory instruments for diamond inspections.
 
Gem Scan Laboratories Certified Diamonds
 

GS Laboratories (GSL) was incorporated in 1985 as an independent gemological laboratory providing unbiased and professional diamond grading and jewelry appraisal services to the jewelry trade and public.

Its Canadian operation in Toronto has grown to become the largest and most prominent diamond grading and jewelry grading laboratory in Canada. GSL Toronto was the first gemological laboratory in North America to be registered ISO 9001:2000. In 2003, GSL expanded into the United States, opening a branch in Dallas, Texas, to serve the American market. In 2006, the company opened its first laboratory in India, located in Mumbai, to provide its services to the ever-growing Indian diamond industry. The success of this lab prompted GSL to expand further in India, with a second lab opening in 2007 in Chennai, India. As of 2007, all branches of GS Laboratories are certified ISO 9001:2000 registered.

All four locations of GS Laboratories are fully equipped with state-of-the-art gemological equipment as well as laser inscription technology for diamonds. GSL is committed to being on the leading edge of the gemological and appraising profession, by continually updating skills, keeping abreast of all gemological advances and discoveries, and investing in continued research and development in the diamond grading and jewelry appraisal fields.

GSL services are utilized internationally by the largest retail jewelry chains, diamond cutters, importers and wholesalers, independent jewelry stores, jewelry manufacturers, law and accounting firms, insurance brokers, and the public consumer.

GS Laboratories, throughout the years and with increasing international presence, has garnered an impeccable reputation as consistently providing the highest quality and most precise grading and appraisal services.

sources: brilliance.com, gslaboratories.com