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Finding good opal rough

rough when there are hundreds of rough rocks. is there a easy way to
pick out the finer pieces or does it take time by looking, like the
more that you see the more you will learn. I found a dozen or so nice
pieces the other night but I’ve never learned how to cut and polish
rock. Three main colors. White, baby blue, and orange. I did find a
fire opal with very nice green and red fire. Would the color fade
after it was cut?

Also, I have two of the cabbing combo machines with 4 or 5 wheels,
and a dual cabbing lathe. Can anyone could suggest a good wheel
combination to help me get from rough to finish. I know that is like
10 or 12 possible wheels. But I mainly use my cab machines to clean
up my castings. This beats a whole day at the bench with a file and a
flex shaft.

Please don’t give me any rough opal sources. I’m not looking.

Brad B.


Most people use no more than 6 wheels, and I’m sure you’ll get other
responses with recommendations for what grit wheels to use. I’d
suggest that you first do some background reading about opal, and cab
cutting in general before cutting a stone.

The Eclectic Lapidary [] has several
articles in the Archives that are available to the public that might
be helpful to you:

Volume I, Issue 3 (two parts), 4, 5 Introduction to Cabochon Cutting
Also in Vol. I, Issue 5 is Hans Durstling’s article “Kitchen Table
Opal Triplets” that discusses the entire opal cutting process… how
to look at rough, orient it, etc. The McCondra Report is in several
issues and many discuss and have photographs of different kinds of

The American Opal Society has a section on opal cutting, and they
have an old piece online that I did on free-forming opal:

There’s a lot of info there, and if you need more, I’ll be happy to
give you additional references online.

Carol J. Bova
The Eclectic Lapidary