Can anyone shed light on GIA/AGS cert numbers?

[thecat]

I recently ordered a diamond with 1xxxxxxxxx cert number (GIA). I found another diamond certed a few days later which is certed 6xxxxxxxxx. I know it's not possible to cert 5xxxxxxxxx diamonds in a few days. Out of curiosity, I asked the JA rep if the GIA cert numbers were dependent on locations which might explain some certs starting with "1" and others with "6". The rep shared that even within the same facility, the numbers differ greatly too. I nearly forgot about my unanswered question till I saw the numbers on these AGS certs.

I was noting down the links and cert numbers to send to my friend when I thought I mixed up 2 of the selections. Upon checking, I realised the AGS cert numbers differed by 20. I thought it should be one or two days apart between both certs. But the 53 one was done in Sep 2017 and 73 in July 2017. How do they assign numbers? Do they just randomize?

I have seen preloved/unsold diamonds being sent back for recert so an earlier number might have a much later date. This doesn't seem to be the case here. I'm curious about the wildly differing GIA cert numbers and the earlier date but later AGS cert number. Can anyone satisfy my curiosity? Thank you.

 

[Karl_K]

The Date is when the grade is final and the report is printed at AGS while the number is issued when it is first graded if not at intake.
If the grade is challenged for a recheck it can be several weeks between the the report number being issued and the report date.
I have no answer to the GIA question, I have noticed the same thing.

 

[ChristineRose]

Possibly a check digit.

There are a lot of ways to do check digits but the easiest is to sum up all the real digits and drop all but the one's place. If you enter a number where the check digit is off from the sum, the computer flags it. No check digit is ever perfect because there are only ten possible choices. Modern computer systems use much more complex rules but check digits in general aren't as useful because they are mostly about typing mistakes.

 

[EvaEvans]

Certificate numbers are not necessary in sequence! The number itself cover much more information than just simple sequence: for example where certificate was issued, which department, etc. The certificate number is in fact a CODE. The same happen with shipping labels and their tracking numbers. The tracking number reveals the origin, the destination, the kind of shipping, etc.

 

[diamondseeker2006]

The bottom line is, the report number is the one number on the report that doesn’t matter. Focus on the numbers on the diamond!

 

[thecat]

The Date is when the grade is final and the report is printed at AGS while the number is issued when it is first graded if not at intake.
If the grade is challenged for a recheck it can be several weeks between the the report number being issued and the report date.
I have no answer to the GIA question, I have noticed the same thing.

Thanks, Karl, for the explanation of AGS number assignment. The discrepancy between dates and number sequences make sense now

The bottom line is, the report number is the one number on the report that doesn’t matter. Focus on the numbers on the diamond!

Trust me, I did second guess my posting of this question as this is one of the most trivial numbers related to any diamond. However, my curiosity won

 

[thecat]

Possibly a check digit.

There are a lot of ways to do check digits but the easiest is to sum up all the real digits and drop all but the one's place. If you enter a number where the check digit is off from the sum, the computer flags it. No check digit is ever perfect because there are only ten possible choices. Modern computer systems use much more complex rules but check digits in general aren't as useful because they are mostly about typing mistakes.

Certificate numbers are not necessary in sequence! The number itself cover much more information than just simple sequence: for example where certificate was issued, which department, etc. The certificate number is in fact a CODE. The same happen with shipping labels and their tracking numbers. The tracking number reveals the origin, the destination, the kind of shipping, etc.

Thanks, Christine and Evans, for sharing the possibilities. I thought numbers were in sequence initially as you find old reports with far fewer digits. It seems they must have included far more information in their current code/number system.

 

[Karl_K]

I pinged a few other trade pros who have more direct dealing with GIA and AGSL than I do.
While GIA itself can tell by the number which lab graded a stone the numbers outside of GIA are intentionally meaningless other than to ID that report.
I also found out I was right that the lab report date for an AGSL report is the day it is printed, and there are several reasons that there may be a time lag between the stone being given a number and the current report being printed.

 

[thecat]

@Karl_K Thanks for making the effort to find the answers to my questions. Why does GIA intentionally makes it meaningless to outsiders/customers? To prevent non authentic certs?

 

[Karl_K]

@Karl_K Thanks for making the effort to find the answers to my questions. Why does GIA intentionally makes it meaningless to outsiders/customers? To prevent non authentic certs?

That is part of it.
Part of it is in my opinion to prevent, this stone was graded at abc Gia lab so it better than one graded at xyz Gia lab.

 

[thecat]

That is part of it.
Part of it is in my opinion to prevent, this stone was graded at abc Gia lab so it better than one graded at xyz Gia lab.

That's a possibility too. Thanks so much for sharing.