A grade in GIA’s Color Grading System…. in the middle of the “Colorless” category.
A movement blank. Typically, an ebauche does not include a mainspring or balance. These items are added as a movement is completed.
European Gemological Laboratory, EGL has franchises in a number of cities around the world which grade diamonds and offer other gemological services. EGL USA Group has laboratories in New York City, Los Angeles, Vancouver, and Toronto. EGL USA is not affiliated with any other EGL labs outside North America. Every certificate issued by an EGL USA lab states “A member of the EGL USA Group”. Certificate numbers are preceded by either “US” or “CA” to indicate country of origin and to provide consumers the assurance that their certificate has been issued by a member of the EGL USA Group. Please be careful of diamond grading reports issued by other EGL labs… they have been known to somewhat inaccurate!
Elapsed Time Rotating Bezel
A graduated rotating bezel often found on divers’ models, used to keep track of elapsed time while diving.
Emerald Cut Diamond
A rectangular-shaped diamond with cut corners. On the crown, there are three concentric rows of facets arranged around the table and, on the pavilion, there are three concentric rows arranged around the culet. This type of cut is also known as a Step Cut because its broad, flat planes resemble stair steps.
The small (usually hollow) piece of metal, crafted to look like a bracelet link, which allows the bracelet to be attached to the case via tiny spring bars.
An artificial process used to improve the apparent beauty of a gemstone. Common enhancement processes include heating and fracture filling.
In a lever escapement, this is the last gear in the train, but does not turn other gears. Instead, it has specially shaped teeth that are alternately locked and unlocked by the motion of the balance and lever to regulate the motion of the watch in a controlled manner.
Allows the power stored in the mainspring to be released through the gears in a regular and controlled manner – See also Lever Escapement.
A GIA and HRD-CGL grade for the highest cut and polish of diamonds.
Irregularities located on the surface of a diamond.
Small facets added to remove clarity characteristics or correct minor cutting discrepancies. Any facet added to the stone which is in excess of the facets normally required to complete the polishing. Usually found along the girdle to remove any imperfections.
A trade term used to describe a diamond with inclusions or blemishes that can be seen with the unaided eye. It is prohibited by the American Gem Society for use by its members. It is also prohibited by the Federal Trade Commission, unless the stone meets the Commission′s definition of the term perfect. I’ve heard it more used in the colored stone trade than the diamond trade.