Need Help Understanding Certifications - AGL, GIA, AGS

[Tigers19]

Could anyone please provide insight on the different certifications out there... AGL vs. GIA vs. GIS. Any insight would be greatly appreciated. The certification is for a Round stone.

Thanks

 

[bagelboy]

Under the Knowledge tab above read the Diamond Grading Reports. GIA or AGS are the only two I would use.

 

[diamondseeker2006]

Most (accurately graded) diamonds will be graded by GIA. You want to search for GIA excellent cut only although some of those are better than others since GIA Excellent is a very broad category. Some vendors use AGS to certify hearts and arrows cut diamonds and other specialty cuts like August Vintage stones because AGS gives a light performance score. You want AGS Ideal cut in that case, although if light return and symmetry are ideal and polish is exellent, that will drop the grade to excellent and those can be a good buy as well (you'll find some of those in WhiteFlash's premium select category). Not all AGS Ideal cut stones are top cut hearts and arrows, either, but they are usually nice stones.

If you find a stone or two that you are very interested in, you can put them on hold with a vendor and then post them here for feedback before you buy. There are many lurkers here, so posting without putting the diamond on hold can be risky!

 

[Gypsy]

For diamonds I would only buy GIA and AGS.

For colored stones AGL is a good lab and has quick turn around.