I suggest comparing some side by side and see which one your prefer. In my limited observations comparing AGS0 and GIAXXX side by side; I have always preferred the AGS0 diamonds. They appear to have more fire and scintillation. The first time I compared them I didn't have a clue who AGS and GIA were; but both my husband and I picked the AGS diamonds as the diamonds we liked the best.
His comment about how he thinks AGS could do a better job of supporting retailers and customers followed immediately on the heels of his observation that AGS does not have "name recognition":You made an interesting comment @MollyMalone. How exactly did this retailer feel "supported" by GIA?
IMO, as a consumer we do not want any independent 3rd party test lab to support a retailer unless it's fast, accurate and low cost test reports.
Labs and retailers need to understand each other but not be intertwined.
What he meant was that AGS does little consumer-oriented "selling". (Odds are that AGS reports with evaluation of cut performance weren't on your radar screen at the outset of your e-ring shopping.) He said there's been a dearth of freshly minted, ready-made marketing materials that a retail jeweler can offer to prospective purchasers re the value of an AGS lab report. What little media advertising AGS has done is generic, of the "visit your local AGS jeweler" ilk:* * * One commented that he'd had a customer bring in a Triple 0 AGS stone as a trade-in & he'd sent it off to GIA to get that lab's piece of paper. As he explained, "AGS just doesn't have name recognition with our customers." He also commented that he thinks AGS does not do a very good job of supporting retail members like himself, and their customers, in this regard. * * *
Doesn't seem we've seen an anecdotal consensus here on PS about that. E.g.,I also think AGS is stricter on color grades
I also think AGS is stricter on color grades
We send hundreds of stones through GIA each year, serving Far East clients in markets where AGS is unknown. Logically there is crossover, where some diamonds initially passing through one lab may be called-for elsewhere and pass through the other.John Pollack had an interesting post about the color grading a while ago. So far as I know, no one has ever sent a bunch of stones to both AGS and GIA and compared the color grade. To do it right you'd need at least 40 stones, possibly more.
If memory serves, you may be referencing this post @ChristineRose? It follows the information provided above.John Pollack's post suggested that AGS is unusual and special, so that when someone sees an AGS stone that has slipped a little, they note it, but when they see a similar slip in the GIA grade they just acknowledge that grades can be one grade off without being considered incorrect. They might send the stone back for regrading and hope the color slips up instead of down.
Who is this John Pollack you speak of?
We send hundreds of stones through GIA each year, serving Far East clients in markets where AGS is unknown. Logically there is crossover, where some diamonds initially passing through one lab may be called-for elsewhere and pass through the other.
This isn't a controlled study, but as intimately acquainted as we are with each diamond I'd submit that our authority regarding our product is more consistent than any outside organization could be. I'd add that our chief gemologist Lieve Peeters is the sole judicial diamond expert for the Belgian Federal police and diamond consultant to Scotland Yard, so we have high confidence in our own preliminary grading.
From our position all labs make mistakes. We recheck grades at any lab, both up and down, based on our authority. For anyone wondering "recheck" is, this post describes the submission and reporting process between the labs and those of us producing diamonds.
https://www.pricescope.com/community/threads/7-4mm-cbi-or-7-68mm-gia-ideal.236887/#post-4273790
The relevant info: GIA grades around 40,000 diamonds per week across nine locations. In worst moments they're off from our assessments by up to 2 grades in both directions. AGSL has only one location and is typically tighter, but tends to swing to one side or the other in specific categories for a while, followed by an internal correction toward center. Whatever the lab, we recheck both ways - up and down - as a matter of brand-protection. Why? Because our retailers cannot order an F from us, have it arrive and be identified as a G, or we'd be sunk. So we're rather sensitive about getting the 'right' grade. And for us, Lieve is always 'right.'
If memory serves, you may be referencing this post @ChristineRose? It follows the information provided above.
https://www.pricescope.com/communit...atural-ags-color-clarity.203189/#post-3698017
Cost and hassle.
Why have two if the majority of your buyers want a GIA or AGS cert. Also many GIA 3x stones get top tier excellent grade but wouldn't make top notch ideal grade from AGS. Although any AGS ideal 0 should easily make GIA excellent.
In some cases it makes sense. I think I would prefer both though. The cost is relatively low. AGS satisfies the small number of people who value cut, but GIA is more well known.
A vendor here many years ago tried duel reports, after spending a bunch of money it was given up.Wonder why more stones don't have dual certificates. Anyone know?
That should have said: My opinion is sadly all color and clarity grading has a resolution of +/- 1 grade at best.My opinion is sadly all color and clarity grading has a resolution of +/- 1 grade.