AAA+ – Very Rare Collector’s Gem
AAA – GbG’s very best Deep Red (or Green, or Bi-color)
AA – Gems are choice Red (or Green or Bi-color)
A – Gems are rich in Pink or Peach hues (or light Green or light Bi-color)
C – Champagne/Clear are lightly toned and clear (sometimes with hint of color)
IF – Internally flawless; free of inclusions
VVS – Very, very slight inclusions; microscopic inclusions barely seen under a loupe with 10x magnification
VS – Very Slight inclusions; inclusions visible only to the scrutiny of the close naked eye
SI – Small inclusions; inclusions easily seen to the close naked eye
I– Heavy or large inclusions obvious to the naked eye
AAA+ — Brightness Rating 5. Very rare collector’s opals.
AAA — Brightness Rating 4. Very bright play of color.
AA — Brightness Rating 3. Bright play of color.
A — Brightness Rating 1-2. Dull or subdued play of color.
C — Common Opal. Brightness rating 0. No play of color.
Our opal grading system is mostly dependent on the level of brightness in a stone, and, secondly, on its natural body tone. The body tone spans from N1 for the blackest of Black Opals, to N9 for pale, translucent Crystal Opals. Brightness is graded on a scale from 0-5 based on the play of color. The brighter the flash, the higher the Brightness rating, and thus the higher the grade. Here is a chart to help you understand how our opals achieve their individual grading.
Body Tone Rating:
The body tone chart shown above separates opals by their natural darkness, thus categorizing them into Black Opals or White Opals (with lots of grayscale in the middle). Within the Black Opal spectrum, an N1 is more highly prized than an N4. If you’re looking for an excellent White Opal, you’d want to choose an N9 over an N7. Our grading system factors all of this in, providing a coalesced idea of worth of the opal for our customers.
0: No Play of Color
1: Dull/Milky Play of Color
2: Subdued Play of Color
3: Bright Play of Color
4: Very Bright Play of Color
5: Brilliant/Collector’s Quality Play of Color
The brightness chart shows the differing levels of play of color, the sparkling opalescence that makes opals so flashy and special, which our brightness scale grades, for our opals. 5 means brightest of bright play of color, and 0 means absolutely no play of color. An opal can have a dark and even colorful body tone (pink, orange, even blue) and still not have a play of color. These stones are also called “Common,” which simply means “no play of color.” Because of this, they are generally graded lower than stones with opalescence, which means a lower price for you for an equally lovely stone!