• Abrasion – A blemish, such as small nicks along the facet junctions.

A blemish, such as small nicks along the facet junctions (look whiter than the rest of the diamond), caused by impact damage. Excessive abrading often a sign that the stone is cubic zirconium, not diamond.

  • AGS – American Gem Society – One of the leading gemological labs.

While DiamondWhisperer grades to GIA standards, AGS is quite close to the GIA on grading standards.See an example of an AGS grading report. It lists the various features of the diamond such as carat weight, clarity grade, color grade, cut grade, fluorescence, measurements and more.

  • Appraisal – An estimation of value of an item, typically for insurance purposes.

While this might be a good guide for the layman, appraisals are rarely, if ever, up to GIA standards for grading purposes. Furthermore, appraisals provide an indication, usually exaggerated, of the retail replacement value of an item, not the re-sale value.

They do however give a rough idea of carat weight, clarity grade and color grade. This is important when it comes to getting an idea of how much you can sell your diamond for on the secondhand market.

Any treatments that a stone has undergone should be disclosed to you at the time of purchase.

  • Asscher Cut See Shape.

Asscher cut diamonds were created in the early 1900s but only rose to prominence in the 1920s. This square shaped diamond has a distinct vintage look and is commonly found in older jewelry. With many similarities to the emerald cut, the Asscher has cropped corners and step cut faceting.