AGS 0, AGS 000 and AGS Triple Zero - Ideal Cut Diamonds
The American Gem Society Laboratory (AGSL) uses a 0-10 grading scale with 0 being the best (ideal). This scale applies to color and clarity grades as well as cutting factors.
Traditionally AGS Triple Zero diamonds were diamonds receiving grades of zero in cut, zero in color, and zero in clarity on a Diamond Quality Document.
- Cut Grade: AGS 0 (Ideal)
- Color Grade: AGS 0 (D)
- Clarity Grade: AGS 0 (IF or Flawless)
Thus, a traditional AGS 000 diamond was a D Flawless diamond with Ideal cut.
Over time, a different usage of the terminology began to emerge. Because of a growing interest in cut quality, sellers began using the term ‘Triple Zero’ in reference to the three criteria that had to be ideal in order for the overall cut grade to be ideal: Proportions, Polish, and Symmetry (pre-2005) and Light Performance, Polish and Symmetry (LP based reports - post July 2005).
AGS 000 diamonds are now understood by the market to be any AGS diamond with an Ideal cut grade, without regard to the diamond’s color or clarity grade.
Cut Grade: AGS Ideal 0
- Light Performance: 0
- Polish: 0
- Symmetry: 0
The increase in this alternate usage at first caused the AGS to redefine “Triple Zero” on their website FAQ, and eventually to remove the question from the FAQ altogether.
According to the AGS, the usage was ultimately allowed evolve into common parlance:
"Technically an AGS triple zero was a diamond with a 0 grade in cut (Ideal), 0 in clarity (IF or Flawless) and 0 in Color (D). AGS 000. However, sellers (internet sellers at first) started calling diamonds with the 0 in cut triple zeros because proportions, polish & symmetry all had to be 0 to get the cut grade AGS 0. AGS tried to address this, but it has entered the modern lexicon. It became an ‘if you can’t beat them, join them’ thing."
The AGS cut grading system for diamonds predated by many years the system now in place by the GIA (Gemological Institute of America). The GIA uses a different methodology and a different grading scale that does not include the term “ideal”. The highest cut grade possible in the GIA system is Excellent. The three cut quality related grades on a GIA report are Polish, Symmetry and Overall Cut Grade. Thus, Triple Excellent equates to the highest grade for cut quality. It is also referred to as TripleEx, Triple EX or GIA EX EX EX.
The GIA provides an overall cut grade only on round brilliant diamonds. The AGS Lab performs cut grading on a variety of diamond shapes including rounds, princess cuts, ovals, emerald cuts and certain cushion cut diamonds.