Opal Buying Guide
Posted: Wed Jan 06, 2016 5:51 am
This is on the International Gem Society's site and is a pretty good article, but it doesn't talk about actual values; it's really about what to look for in opals, and how to rate them according to the standard. It seems to cover all the bases so I thought y'all might like to take a look at it.
The only problem with their site is the stupid pop-up ad that blocks your vision when reading, so if you don't have a blocker for them you'll have to refresh the page to get rid of it for a while. I hate sites that do that to me, and I can't even see the X to close them because it's too far up for me to click it.
"Opal gemstones are evaluated a little differently than other gemstones. The International Gem Society opal price guide features a grading system and terms unique to opals. A full description of these differences can be found in our Premium article on Appraising Opals. For the benefit of those interested in opal buying, here is a brief explanation of these terms.
Opals have grades of below commercial, commercial, good, fine, and extra fine. These assessments cover an opal’s colors, directionality of flashes, imperfections, and cut.
Body tones, from N1 (black) to N9 (white), describe the base color of a stone, without play of color. This system is used to distinguish black, dark, light, and white opals. Stones from N1 to N4 are considered black opals. N5 to N6 are considered dark opals. N7 to N8 are considered light opals. An N9 is considered a white opal.
Opal Buying And The 4 Cs ...."
https://www.gemsociety.org/article/opal-buying-guide/
The only problem with their site is the stupid pop-up ad that blocks your vision when reading, so if you don't have a blocker for them you'll have to refresh the page to get rid of it for a while. I hate sites that do that to me, and I can't even see the X to close them because it's too far up for me to click it.
"Opal gemstones are evaluated a little differently than other gemstones. The International Gem Society opal price guide features a grading system and terms unique to opals. A full description of these differences can be found in our Premium article on Appraising Opals. For the benefit of those interested in opal buying, here is a brief explanation of these terms.
Opals have grades of below commercial, commercial, good, fine, and extra fine. These assessments cover an opal’s colors, directionality of flashes, imperfections, and cut.
Body tones, from N1 (black) to N9 (white), describe the base color of a stone, without play of color. This system is used to distinguish black, dark, light, and white opals. Stones from N1 to N4 are considered black opals. N5 to N6 are considered dark opals. N7 to N8 are considered light opals. An N9 is considered a white opal.
Opal Buying And The 4 Cs ...."
https://www.gemsociety.org/article/opal-buying-guide/