Searching for a marquise - how can I get the crown height % ? Etc...

[2Bmarried]

OK.....

I was trying to put the knowledge I''ve learned from this site to good use as I offered my old roommate some help in searching for a diamond for an e-ring. Problem - I did all the looking and research for myself on rounds a few months ago. Of course, he wants a marquise! I''ve been trying to view all of the relative posts on marquise stones, but still have some questions. One good thing, though, is that I''ve gotten over my fear of fluorescence by reading a bit more here!

After checking David Atlas'' cut grades on marquise, I set out to find one within the specs given for 1A. It''s a bit harder than finding a round within the 1A class! I''ve come across one I think he might like, and I know there will be no substitute for actually seeing it, but it "looks good on paper". The L x W ratio is pretty tight, too. It gets all 1A specs except for the crown height %, which is, of course, undetermined & (from what I''ve seen) non-existent on the GIA reports. (By the way, I want to find a GIA graded stone.) I tried to input the data to DiamCalc, but I''ve been having a hard time adjusting values, etc. Any way I can estimate the crown height successfully?

There is no Sarin nor similar report on this diamond from DCD, so I cannot get any more data for the calculations. Help from any experts would be appreciated. Maybe I''ve seen all I need to see through the computer & now we just need to see it in person?!

DCD marquise

$3000 is his price max for the diamond alone, & D-F / VS2 are what we''re shooting for.

As always, feel free to smack me around a bit if I''m overlooking anything elementary!!

Thanks!

 

[2Bmarried]

Any vendors have a Sarin report or anything with the crown height percentage for a similar sized (3/4 ct marquise) diamond??? Trying to get all the facts together so I can make a more informed decision.

Thanks

 

[valeria101]

Allot of marquizes are not very brilliant - to say the least. I would use the AGA first three slots to get a selection and look for a stone with decent sparkle. If AGA A1 is hard to find... it might not feal good if the stone turns out s real dog in the light return department. My fealing is that this remains quite probable and woudl not be great news.

I would most likely be more lenient about getting a Sarin on these (since it still does not tell me anything on light return) and look for the good ol' table, depth, symmetry (congrats for finding a VG - it would make a good point to start) and L:W proportions. If your friend wants one of those slender marquizes (2:1 or more) some attention should be paid to how table and depth % are computed - 70% depth means very different things in a stone of 1:1 and in a 2:1 !

Conclusion? Would it be possible to have a seller select a stone based on light return for you? GoG's stones are the Expert Selection at WF would oblige, I suppose.

For Example... not the greatest match to your specs, but there could be more where this one comes from