Was searching for info on minerals and came across this.
Gem Stones of the United States - The government stamp reads, I believe, March 3, 1949
Geological survey bulletin.
http://pubs.usgs.gov/bul/1042g/report.pdf Many of you have probably seen it but for those who haven't it's interesting.
Especially the geographical distribution of deposits.
Love reading old technical publications.
James
