For stones, I have been thrilled with Boston Gems & Finding, Inc. 333
WASHINGTON ST. RM. 543, BOSTON, MA 02108 USA. 617-742-9402
800-225-2436 FAX 617-742-9592 They are members of AGTA- Quality
merchandise, lots of calibrated goods and one of a kind as well. They
are wholesale only (you need a tax # to order from them- they may
sell to students as well, I'm not sure). They will let you know what
is treated and what is not. Extremely nice folks, honest. The
building they are in 333 Washington Street, is full of jewelry
businesses, including tool dealers.
PS. Oooops! I forgot to mention that Boston Findings also has a full
line of findings as well!
HTH, Kate Wolf, in Portland, Maine
hosting quality workshops. http://www.katewolfdesigns.com