"European Gemological Laboratory Defines SI3"
by Thomas E Tashey, Jr and Gary A Roskin
The clarity grade SI3 has been used consistently to describe lower SI2 and the higher I1 clarity grades for diamonds.
Click here to read more about why this was the logical addition to the diamond grading scale.
To keep you abreast of new discoveries in gemstone research, synthetics and treatments, we have listed a selection of informative articles written by experts in their field. Check this page regularly for updates.
'The Scoop on synthetics'
Can we ID them? Should we grade them? Do we need them?
Should a man-made diamond be called "synthetic", or "cultured" and who are the important players in this controversial addition to the diamond industry?
"A Gemological Study of A Collection of Chameleon Diamonds"
The rarity of chameleon diamonds and their interest for the connoisseur are due to their unusual ability to change color temporarily when heated to about 150C, or after prolonged storage in the dark.
"Interpreting Diamond Morphology" - Part I
A diamond's morphological features reflect conditions of diamond formation and represent a unique characteristic than can be used to identify details of the sources of diamonds.
"Interpreting Diamond Morphology" - Part II
Morphological features reflect conditions both during diamond formation and also after emplacement, especially where alluvials are concerned.