Some of AGS negligible fluor stones = GIA faint?

[Dancing Fire]

If that is true should these stones be priced lower than the ones graded GIA none?

 

[diamondseeker2006]

I personally don't see what faint or negligible would have much if any impact on price. However, I am not the diamond pricer!

 

[missy]

I'm with @diamondseeker2006 Dancing fire. If it is negligible it would have a negligible effect on pricing don't you think?

Some of AGS negligible fluor stones = GIA faint?
If that is true should these stones be priced lower than the ones graded GIA none?

 

[Johnbt]

They're the same thing - somewhere from none all the way up to too little to matter. Look it up.

Okay, I did...

www.briangavindiamonds.com/news/ags-negligible-fluorescence-vs-gia-none/

 

[Johnbt]

And from Whiteflash...

"There is a slight difference between AGSL and GIA in the way they report on fluorescence. GIA uses two distinct descriptors “None” and “Faint” for diamonds with minimal fluorescence whereas AGSL combines the two in the term “Negligible”. Therefore it is possible in some cases that diamonds deemed “Negligible” by AGSL can have minor levels of fluorescence detectable under UV light."
_____________________________________________________________________________________
neg·li·gi·ble
ˈneɡləjəb(ə)l/
adjective

1. so small or unimportant as to be not worth considering; insignificant.

 

[John P]

AGSL omitted the term Faint just prior to 2000, so their Negligible grade covers a sliding scale of none up to the lowest level of medium.

That decision was made as the grading of Color and Fluorescence at other labs was coming under fire for inconsistencies. Over the years this has involved allegedly-unreported policy/equipment changes and growing location-based variance. The main challenges continue to be non-uniform tubes, strength of UV, filtering and distance - among other things. Those in the trade are well aware that the inconsistencies continue to this day. In that context the AGSL approach is a realistic one.

Those who like spectrophotometry should Google "Martin D Haske GIA Fluorescence" for more. Print the resulting pages. Set down Isaac Asimov and curl up next to the fire with Marty. You might want a glass of wine.

 

[diamondseeker2006]

Those who like spectrophotometry should Google "Martin D Haske GIA Fluorescence" for more. Print the resulting pages. Set down Isaac Asimov and curl up next to the fire with Marty. You might want a glass of wine.

I think I'll just have the glass of wine. Your explanation was good enough!

 

[Lorelei]

AGSL omitted the term Faint just prior to 2000, so their Negligible grade covers a sliding scale of none up to the lowest level of medium.

That decision was made as the grading of Color and Fluorescence at other labs was coming under fire for inconsistencies. Over the years this has involved allegedly-unreported policy/equipment changes and growing location-based variance. The main challenges continue to be non-uniform tubes, strength of UV, filtering and distance - among other things. Those in the trade are well aware that the inconsistencies continue to this day. In that context the AGSL approach is a realistic one.

Those who like spectrophotometry should Google "Martin D Haske GIA Fluorescence" for more. Print the resulting pages. Set down Isaac Asimov and curl up next to the fire with Marty. You might want a glass of wine.

I like it.

 

[HappyNewLife]

My AGS negligible ACA has what looks to be almost medium blue fluor. At first I was annoyed, but on the other hand it doesn’t impact my diamond at all.

 

[HappyNewLife]

 

[Rockdiamond]

Excellent explanation John!
Without a doubt, specifying the intensity- and even color of fluorescence is one of the thorniest aspects of diamond grading.