Selling Your Diamond: Maximizing Value & Finding Trusted Buyers

Question
I have a 2 1/2 carrot pear shaped diamond set in platinum that was appraised for $11,000. I have lost the appraisal document.  Last year I was in a jewelry store in Utah and the jeweler said that if I were to sell it that I should not accept anything less than $8,400.00  I have since tried to sell it with no luck, being only offered 1,000 Euro. (I live in Germany)  Who can I trust and which is my best option in trying to sell it?  Thank you for your time.

Answer
Hello Kathy,
I know in the United States the best way to determine the value of a diamond is to send it to the GIA that is the Gemological Institute of America... they're located in Carlsbad California... they will not give the value but do a complete gemological report which is accepted by dealers as perhaps the best assessment... also if it is a valuable diamond for a small amount they will give it a serial number into the diamond using a laser.. this is very important since it attaches that diamond to that report and also at the diamond will not be switched on you... I think the GIA has offices in Europe..
find them on Google and you can e-mail or easily call them.. if I can help any more let me know regards Rolfe