A recent patent (US 6,473,164) issued to GIA on October 29, 2002 goes to great lengths to call into question any and all techniques previously used for color grading diamonds. But, as typical with GIA, they don't do their homework even though they say they are "the world's foremost authority in gemology"TM .
The patent devotes a paragraph to the SAS2000 stating "An Adamas system, which performs color analysis and deploys a spectrophotometer, has been developed. However, the Adamas system illuminates through the table of the diamond, utilizes an integrating sphere and analyzes color using a single, static measurement. The instrument does not approximate visual color analysis methodology, and does not meaningfully correlate the results to historical precedents of visual color analysis".
"Meaningfully"?, they forget that SAS2000 color grading works!
Gee, I guess the weenies who authored the patent weren't there or never bothered to listen when I gave a presentation on the SAS2000 to GIA research personnel a few years back at Carlsbad, but characteristically of GIA, or their cronies, denigrate anything "not invented here". In fact, the authors may not have even seen an SAS2000. I know they don't know what is going on in the software! Let us say at this point, before the attorneys get to it, that GIA's statement above about the SAS2000 is WRONG, period, end of discussion.
GIA's reckless and irresponsible primary statement "the Adamas system illuminates through the table of the diamond" is factually wrong, and misrepresents our process. Other statements regarding the SAS2000 Spectrophotometer Analysis System which follow the above misrepresentation are also wrong and further misrepresent our process. Their clearly false statements of "fact" does irreparable harm and damage to the SAS2000 Spectrophotometer Analysis System and Adamas Gemological Lab.
SAS2000 color grading is the most accurate methodology available today, or in the foreseeable future, based on sound scientific principles and analyses derived from color science, which included the modeling of human color vision and human color adaptation. It also uses a (removable) filter to eliminate the UV effects from fluorescence in color grading diamonds, something which was taught for over 50 years by GIA "diamonds should be graded at their poorer color in artificial light devoid of ultraviolet".
Their patent also makes false claims about what they actually do, or attempt to do. They continually claim that they measure the reflected light from "a specific angle relative to the table of the diamond", as if that makes a difference. But, just because they position their probe at a fixed angle with respect to to table, that doesn't mean that they only measure light at that angle. A zero angular deviation for optical acceptance angle is extremely difficult to do, in fact I doubt it is physically realizable. Furthermore, I don't know of any person (other than one nearly blind), diamond grader or otherwise, who has zero peripheral vision, which is what, effectively, they tout. More on "their methodology" later. Oh, by the way, what angle are they looking at: A or B?
Figure A: GIA Diamond Grading Course 1995
Figure B: GIA Diamond Grading Course 2002
One might only look to GIA teachings over the last 50 years to establish "historical precedent". The above referenced patent by GIA continuosly makes reference to "daylight approximating light source", while "historical precendence" is established (see Fluorescence Article) by GIA teachings "filtered, cool white, ballanced fluorescent light is best; unlike sunlight, it is nearly free of ultraviolet". In fact, for fifty years GIA effectively taught to "grade diamonds at their poorer grade in artifical light devoid of ultraviolet" . The SAS2000 filters out the ultraviolet compenent of its light source, although the filter is removable.
ADDITIONAL GIA METHODOLOGY
I guess I would have to admit that the SAS2000 does not completely grade diamonds ( unlike the invention described in the above referenced patent and filed on February 14th, 2000, which purports to grade diamonds the GIA way ), according to complete "historical precedent". The SAS2000 did not, and currently does not have a "Benefit of the Doubt" (BOD) button, although one could easily be put in the SAS2000 software.
According to GIA (GIA Diamond Grading Courses 1989 and 1995, Assignment 10, "Fair is Fair"), GIA teachings were: "In general, when a diamond is on the borderline between two grades, deciding whether or not to give it the benefit of the doubt depends on whether you are buying or selling. Certainly, when you are buying the price is likely to be based on the highest possible grade." GIA goes on: "On borderline cases, many good appraisers think it better to go with the higher grade. This reinforces the inherent value of jewelry in general, protects the interests of those who invested in it (we all benefit from public confidence in the industry as a whole), and respects the good faith of the dealer who sold it in the first place."
Well, I guess I'm not a good appraiser by GIA's standards, in that I do not intentionally bias the results to the benefit of the trade, and to the detriment of the consumer. No "Benefit Off Doubt" button!
NOTE: (In 2002, these highly offending statements were removed from the GIA Diamond Grading course, at least I could not find them.)