Last updateTue, 19 Jun 2018 9pm

Joseph W. Tenhagen, NAJA Associate Director, Passes Away


Joseph Tenhagen passed away on April 27th at the age of 79.  Joseph spent forty years as an appraiser and consultant to the gem trade and jewelry industry.

He attended the University of Miami as a Geology Major and then earned his Graduate Gemologist diploma from the Gemological Institute of America in 1969.  In the same year he earned his Fellowship FGA diploma from the Gemmological Association of Great Britain. 

Tenhagen-JuneHe joined the National Association of Jewelry Appraisers (NAJA) in 1992 and served as Associate Director when Dr. James Jolliff was Executive Director as well as with the current Executive Director, Gail Brett Levine.  Mr. Tenhagen earned is Master Gemologist Appraiser title from the American Society of Appraisers from 1983 to 1995. 

Joe Tenhagen published the “Diamond Value Index” from 1995 to 1998.  He was also on the Editorial Advisory Board for Precious Stones Newsletter, and published many articles in Gems & Gemology, Lapidary Journal, and NAJA’s The Jewelry Appraiser as well as Precious Stones Newsletter.

His participation in organizations and professional societies was equally prodigious.

He was a frequent panelist and presenter at GIA Symposiums, ASA, and NAJA.  He was a Charter Member, Past President and Past Secretary of the Diamond Dealers Club of Florida until 2005.   From 1981 to 1984 he was President of the Accredited Gemologist Association.

Additionally he was a Senior Member and the Associate Director of the National Association of Jewelry Appraisers (NAJA) from 1992 to present.  

He is survived by his wife Mary, his son Tom and his wife Theresa and two grandchildren, Beverly and Joey.