Diamond Grading Labs – A Plan for Peer Review

[pricescope]

Here is what Garry is going to talk about at GIA Symposium: Diamond Grading Labs – A Plan for Peer Review

 

[Regular Guy]

Well...break a leg, as they say!

What is the intention ... to just display here, or also gather comment?

I can't resist the latter.

Where you say:

"Report stones by sending their details to the e-mail address below (remain anonymous if you wish). Details will be posted on a closed private Intranet Forum, so that no labs are alerted. The volunteer experts (independent of major labs) may want more information, or the stone might be needed for further testing. If the committee believe a 2 grade error has been made, the diamond will be sent anonymously to various labs (and possibly back to the same lab). If a stone has 2 grades (or 3+ AGS cut grades) difference, the reports will be published on www.Pricescope.com and made available to news media and trade magazines."

Is the idea that naturally occurring mistakes would be submitted? If so, no concept of an error rate is imagined, right? Just that the possibility of 2 grade differential happen at all is the threshold of note?

But, under any system, even for a 2 grade differential (standard for EGL we read, and punishing for as many as 4 appraisers on this board who I think owe the submitter cashola)...isn't some error rate conscionable? If so, what's the point of observing naturally occurring outliers, if there's no basis for understanding with what frequency they occur?

 

[Garry H (Cut Nut)]

Good points Ira.

We do not know if anyone will offer to send stones to us at all yet - so we do not know about the idea of doing any stats that would be meaningful.

But we shall see.

I personally think there are less bad gradings in color and clarity than we hear about all the time.

But if there is a large number of really soft grades from 1 or more labs out there then i hope we can entice them to tighten up a little.

Alternatively there may be examples of overly harsh grading. I hear reports that labs might do this to get additional fees for rechecks.

But the main reason to do this is to see if those who winge can really substantiate their winge-ing.

 

[JulieN]

INTRANSITIVE VERB: Inflected forms: whinged, whing·ing, whing·es
Chiefly British To complain or protest, especially in an annoying or persistent manner.

 

[strmrdr]

interesting.....
good luck.....