THE SARIN TECHNOLOGY

THE SARIN (GIA FACETWARE REPORT)

Sarin Technologies Ltd. is perhaps the largest manufacturer of non contact measuring devices in the world and they produce 5 different versions of scanners. All of them are single lens scanners except for their most advanced model, the Sarin DiaMension which uses interchangeable lens allowing the user to scan diamonds from 1mm to 28mm in diameter (.01ct and up to 70ct polished diamond).


The Sarin Diamension is the scanner of choice for such labs like GIA, AGS, HRD, IGI, and other leading labs and manufacturers around the world. We are proud to be among the clients who own this as well as we seek to squeeze all the information we possibly can from the Sarin to utilize in helping our clients both in store and via the Internet. Sarin has cooperated with firms such as ours and has produced a Sarin Web Viewer which anyone who owns a PC with MicroSoft Internet Explorer 5.0 and above can take advantage of.

Here's a screen shot of a diamond seen in 3d mode via the Sarin Web Viewer. This shot shows us the basic average measurements of the main facets of the diamond it has scanned.

Here's the same graphic but marked off explaining the measurement being taken.

While this may seem like quite a bit of information we're only scratching the surface. This is only giving us the average measurements of 17 out of 57 facets plus girdle and culet information. There are 40 other facets that must be taken into account if we want to chew the whole enchilada and get an idea of how this diamond can truly appear in real life. Thankfully this isn't the end of the info we can attain with the Sarin.

If you note in the above example many averages are listed. Let's take the crown angles for example. In this diamond the average crown angles are 34.2°. This average is arrived at by measuring 8 crown main facets. We can see the measurements of each crown facet in 2 different ways.

1. You can click and drag this 3d model and rotate it to the face up position and click on each facet. Doing so will show us each facets individual angle (see below).

Or for an easier quicker way we can click on the dropdown "View:" menu atop of the viewer and pull up the Manufacturer's Report. This gives us most of the numbers at a glance. Here we can see in spreadsheet format the average measurements for each facet set including their minimum and maximum measurements and all of their individual angles/measurements as well! Note the top row.

Cool stuff eh? So ... what exactly does this tell us about this diamond? Right off the bat it gives us an idea of how precise or how sloppy this diamond was cut. Here are some of the primary things I look at on these numbers.


   Minimum Maximum  Variance 

 Crown angles

 33.9°

 34.5°

 .6°

 Pavilion angles

 40.7°

 41°

 .3°

 Table %

 56.4°

 56.6°

 .2°


On the primary angles and table measurements of this diamond it has some very tight variances. The highest variance is .6° on the crown angles. Nothing to worry about especially considering the pavilion angles are more important. These numbers indicate evidence of excellent precision.

Let's compare that to another more commonly cut stone.

   Minimum Maximum  Variance 

 Crown angles

 30.5°

 33.5°

 3.0°

 Pavilion angles

 41.5°

 43.3°

 1.8°

 Table %

 57.4°

 58.7°

 1.3°



Not very tight.

Before we review the Reports you can see within a Sarin file we do provide a screen shot for Mac Users which you can not view within the Sarin file and that is the GIA FacetWare results as shown to us via our Sarin Machine in our lab. On the FacetWare Report is listed additional facet information such as Star facet length and lower half length. If an individual is going to utilize GIA's FacetWare program (free on their website) a knowledge of all of these facet measurements are necessary in estimating a GIA Cut Grade. One primary limitation to the FacetWare program is that you also need to know details of ...

a. The girdle cutting to accurately determine a true GIA Cut Grade. For our article on girdle cutting I refer you to our chapters on Painting and Digging.
b. You also need to know the Polish and Symmetry Grade (must be a minimum of "very good" to get the Ex cut grade).
c. The girdle and culet size. This is given on the Sarin Report but GIA wants a verbal confirmation as well.

We check for each of these additional features on all our diamonds and disclose this information to our clients before the purchase as they are listed on each diamonds page.


Here's a quick summary of the Reports and data you can view in a Sarin 3D file.

1. The first screen brings you directly to the 3D model.

There's a bit of information we can gain from the 3D model.

a. Three of those features relating to the girdle is being able to determine whether a diamond has a classic girdle, painted or dug out. You can read about how that's detected at the link above. b. Another feature being able to see the angle of any individual facet as demonstrated above. c. You can also see certain symmetry characteristics/deviations. Compare the models of the 2 diamond below.

2. The next screen shows symmetry via a wire frame model. A model that you can also rotate in 3D view.

3. The cut grade results via AGL laboratories. Excellent is their top grade and a symmetry grade of "Very Good" is the highest grade the Sarin can assign to a diamond primarily based on the variances we discussed above. The diamond below has very tight variances as indicated by the "VG" grade for symmetry plus you can see the min/max crown and pavilion angles on this report. .2° variance in the crown angles and only .3° on the pavilion mains.

4. The cut grade results via AGL laboratories.NOTE: These are the results under the old AGS Cut Grading system. If we assign a cut grade via our search engine it is based on the new system.


5. Cut information of what HRD looks for. HRD is perhaps the most popular European lab in the world and holds a good reputation among trade members overseas. This particular page in the Sarin file, to me is useless since it doesn't give their grade.

6. IGI Cut Grade Results. Lots of good info on this report including all "Dev" deviation measurements on each of the facet sets. IGI happens to be the first lab to include Hearts & Arrows reports which you can read about on their website.

My favorite which is the "Manufacturers Report". It reports all facet information with the exception of lower half (or lower girdle) and also upper half (or upper girdle) information.


I've personally taken care of that problem however and have developed a customized manufacturers report which we use in our lab for the checking of these additional facets.

The rest of the reports give proportion and facet information for FANCY shapes, Cushion, Oval and Princess cuts.

The Sarin Web Viewer also allows you to save individual files of stones you like inparticular and allows you to print and view any file you have open or saved. On top of these features we have the ability to import Sarin files into other 3D modeling programs which we will explore in our Chapter on the Gem Advisor which allow us to view certain optical information about the diamond which is very valuable in our exam.

If there was one thing I would like to see improved about the Sarin, it would be it's modeling capabilities. If you examine a 3d model in detail, a close examination reveals minor flaws in the scanning process.