Yohannes, you forgot to mention the companies you've tried. Here are some
sources for large quartz wafers:

P.R. Hoffman Materials Proc. Corp.
321 Cherry Street
Carlisle PA 17013
Tel 717-243-2011
Fax 717-243-1672
POCs: Galen E. Martin, sales mgr, Ken Casey, Pres.

Sawyer Crystal Systems
1601 Airport Rd.
P.O. Box 2707
Conroe TX 77301
Tel 409-756-8886 or 8887
POC: Kelley Scott

VALPEY-FISHER Corp.
75 South Street
Hopkinton MA 01748
Tel 508-435-6831

Good luck...............John.
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           John R. Vig
           U. S. Army Research Laboratory
           Attn: AMSRL-PS-ED
           Ft. Monmouth, NJ 07703-5601, U.S.A.

Telephone: 908-427-4275,    FAX: 908-427-4805
Internet: JVig@ARL.mil
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