Opal Buying Guide

Ask the pro's for a guesstimate of your opal value here

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PinkDiamond
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Opal Buying Guide

Post by PinkDiamond »

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. :roll:

"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/
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SwordfishMining
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Re: Opal Buying Guide

Post by SwordfishMining »

Nice share. I found "The Guide" to be the most expansive pricing guide I've come across so far. Brazilian, Mexican, Boulder & Matrix are separated from Gem Opal and Fire Opal. I have to do something for a local specific matrix I can just look at my stone and ballpark a multiple for price per ct. I sort into 27 categories/grades of mine fresh so it does take awhile. Let alone the which mine or pit it came out of. Thats just to wet gem & dry gem to wood specimens not any thing on percentages or quality of that percentage.
Changing the grading, the brightness in particular, to more grades than before -makes sense with a wider range of possibles to allow top ranking for the actual quality's of top ranking, but the try to get it to match the black scale numbering instead of putting two more grades on top of all their PR work (and existing systems not changing) done making the old 5s the best in the world. I'm going with the tried and true and advantageous to me new when we see what 5 stone vs 7 stone grading cards look like. Less black grades to a single white one and no translucency chart- A 5 step would be better than a 3 or 7 step I think.
Another of my dilemmas as I have the entire range in gem opaqueness with various body colors, with a distinct lack of volume in the topmost ones, say Teal Blue or Easter Pink with plume play of fire in a dry black over an oz. Probably due from me not having even 1 kilo of pure gem to go thru a year instead of thousands of kilos politicking instead of being mining. Now mind you thousands of cts go into rockhound collections each year and most cant bring themselves to cut down that cast specimen into only a gemstone when it is not promised to work out well. Wah Wah WAh says the new puppy Gemma, a white Shepard! It'll pack right in with the rest no worries 3 1/2 months old, cant be 40 lbs yet LOL.
I'll jump over my shadow. https://www.virginvalleyopal.com"
Opals & more at my ESTY store https://swordfishmining.etsy.com"
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