Edited and Published by Hale Sweeny
Web Site:
Associate Editors: Geo. Butts, JR Shroeder, Steve Henegar,
Margaret Malm, Sam Todaro, and Ed Elam

This list digest contains the following message subjects:

1. LapDigest News for Issue No. 287 - Sat 3/10/2001
2. NEW: How to Make a Pyrite Sphere Sparkle
3. NEW: Druzy Backing
4. NEW: Need Tips on Working Black Coral
5. RE: Information on Shahuckite (or Shattuckite?)
6. RE: Information on Shahuckite (or Shattuckite?)
7. RE: Information on Shahuckite (or Shattuckite?)
8. RE: Information on Shahuckite (or Shattuckite?)
9. RE: Information on Shahuckite (or Shattuckite?)
10. RE: How to Cut a Preform for a Sphere Machine
11. RE: How to Cut a Preform for a Sphere Machine
12. RE: How to Cut a Preform for a Sphere Machine
13. RE: Will Sanding Silver Hurt My Lapidary Wheels
14. RE: Will Sanding Silver Hurt My Lapidary Wheels?
15. RE: How to Polish Black Onyx?
16. RE: Polishing Glass/Obsidian on Vibrating Tumbler
17. RE: How to Clean Spots from a Crystal
18. RE: FS: Books on How-to-build Lapidary Equipment
19. WTB: Slab/Trim Saw


Subject: LapDigest News for Issue No. 287 - Sat 3/10/2001

There is a new e-mail list, named RockhoundList, which is
moderated by Bob Keller (of Bob's Rock Shop), and is a
discussion group for mineral and rock collectors and those
with general interests in mineralogy, geology and the Earth
sciences. To join, go to
fill out the form.

A BIO for Trevor Berry appeared in the last issue. I just
received a note from Dennis Marinac <>
commenting on Trevor; Dennis says: "(snip) I consider Trevor
Berry as one of the top 10 Opal cutters in the WORLD. I am
very grateful that he is a member of the Digest and I have
personally learned a lot from Trevor." Welcome, Trevor.
You certainly have a friend and admirer in Dennis; I hope
will enjoy the Digest and will help us all with your opal
cutting knowledge.

You guys have a great week!! (Please note that when I say:
'guys', I am using this as a generic for 'friends'!) My
Japanese weeping maple is in full bloom, Bradford pears and
Dogwoods are blooming and it is BEAUTIFUL outside!! Enjoy
all the springtime beauty with those you love, and remind
them of your love strongly and often!!!


Subject: NEW: How to Make a Pyrite Sphere Sparkle

Hi, Hale -

I need information on how to put the sparkle back on a
pyrite sphere.

At Quartzsite this year, I picked up a couple of magnificent
Peruvian massive pyrite spheres, each with cavities lined
with cubic pyrite crystals. They were as shiny as mirrors
and almost put your eye out in the sun. However, they
apparently didn't take too kindly to oils from my hands and
have lost some of their sparkle.

I would like to ask your subscribers if anyone knows how to
perk up the original luster so I can get that knockout shine

Thanks for your help.

Subject: NEW: Druzy Backing and

I am just starting to learn about stones, & have fallen in
love with Drusy. At Tucson I purchased some azurite, some
dendrite, and some onyx Drusy. I understand it is too
fragile to set for rings, but what about earrings or a

The backs of all the stones look the same, a smooth brownish
black perhaps 2mm thick coating. What is that ? Is it
durable, will it withstand water?


Helene S-French

Subject: NEW: Need Tips on Working Black Coral

Hi gang!

Our mineral club had an auction last night and I picked up
some nice solid black coral. I can't wait to get started.
But first, I thought I'd ask for tips. Also I'd like to
know what the stuff is currently worth. I did check the
thread list, but found no joy.

I remember back in the '70s, black coral heshi and inlay
was every bit as popular as turquoise and puka shells. I
just don't see it offered at gem shows anymore. I do know
that there are collecting bans in place and that old
collections are about the only source. Any tips would be
greatly appreciated.

Yours in Boulder,
Paul Boni

Subject: RE: Information on Shahuckite (or Shattuckite?)

(Hale's note: This is from the originator of this thread,
in answer to some questions I asked him.)

Some of the material I have is massive, up to 6 pounds so
far, and some small 3 to 4 ounce pieces with a thin layer
of calcite on outside. It is a brilliant sky or electric
blue. Some of it has a vein of a nice medium shade of green.
There are a few stones that are a light olive green. These
stones were found in West Africa. It cuts and polishes

I have quite a bit available. I'll try to scan a few pieces
tomorrow and send you pictures,


Subject: RE: Information on Shahuckite (or Shattuckite?)

About Shattuckite, it was named for a famous mine in Bisbee
called "The Shattuck Den"

It is fundamentally similar to a mixture of Malachite and
Azurite. It has a hardness similar to the softer turquoise,
and can be cut and polished in the same way.

After cabbing to shape, ending with a 220 grit, I do the
final polish with a felt wheel and a Bruce Bar (Fabulustre).

Dave Childers

Subject: RE: Information on Shahuckite (or Shattuckite?)


What you possibly have is chrysocolla as that comes in an
electric blue color. Shattuckite is a rare copper mineral
related to Azurite and Malachite and is a dull, steel gray
or blue color usually in a massive form. I have several
specimens from different locations.

If you go to the following location you will find
information on Shattuckite:


Subject: RE: Information on Shahuckite (or Shattuckite?)

I have some beautiful pieces of shattuckite that, for some
reason I never get around to setting. I think that the rock
may be so pretty, I'm intimidated... It is gorgeous. I have
some rough that I got from a friend who picked it up in
Utah. It looks similar to chrysocolla, but it is a harder
material with fewer soft spots. I had no problems working
with it myself. It takes a great polish with cerium.

I have a digital camera now, so I could e-mail some pictures
of shattuckite if anyone is interested.


Subject: RE: Information on Shahuckite (or Shattuckite?)

True Shattuckite came from the Shattuck mine in Bisbee,
Arizona, some 35 years ago. As far as I know, the mine has
been closed for over 30 years.

I have an egg from Africa that is called Shattuckite, but
it is a "pretender." The Africa material looks like
chrysocolla with some hematite mixed in. I have several
true Shattuckite pieces that came from a man who collected
it at the mine in Bisbee. It is a copper associated mineral
and looks a little like lapis. I polish it like lapis and
use chrome oxide in the final polish. My pieces have a
hardness of 7-1/2, and make a beautiful stone.

Robin Pascal


Subject: RE: How to Cut a Preform for a Sphere Machine

I have some info on sphere cutting at my website, but it
uses a cube as the starting point. The reasoning behind
this will help solve your problem.

Find a large square (cube) perky box and a tennis ball that
just fits inside it (or use a small one and a marble, or a
medium one and a Ping-Pong ball). Put the ball inside. To
make a preform you cut the corners off the cube to better
approximate the shape of the sphere. Having a ball in a
clear box makes it much more obvious.

It works for an irregular piece too. Just use the narrowest
dimension as one pair of faces on a cube, trim the other
two sets of faces to make a cube, and then trim corners if

Kreigh Tomaszewski

Mailto: <>
Please visit our family web pages at

Subject: RE: How to Cut a Preform for a Sphere Machine

Personally, I eyeball the rough piece, and cut the cube with
the final sphere size in mind. Keep in mind that none of the
original cut surface of the cube will survive the remaining
20 cuts and grinding process; in fact only the center of
each face of the cube needs to be at the surface of the face
of the cube. I know that sounds confusing, but with practice
you can cut your "cube" to maximize the diameter of the
sphere for the piece of rough. The only problem you may run
into is fitting the piece in a 45 degree jig to make the
remaining cuts, if you use a jig.

Your other alternative is a core drill; you will generally
waste less with this method of roughing out spheres, but the
waste is more or less unusable, unlike the waste from a slab

Tim Fisher
Web Site:

Subject: RE: How to Cut a Preform for a Sphere Machine

Re Bob Redden's question about how to preform a sphere,
there is a neat little book out titled, A Gem Cutter's
Handbook, Specialized Gem cutting by Jack R. Cox and
published by Gembooks. Mine was published in 1970 but I
believe it has been published several times since then.
There is an entire chapter there about how to prepare your
material for making spheres.


Don Dietz

Subject: RE: Will Sanding Silver Hurt My Lapidary Wheels

I have used expandable drums for sanding silver. It works
fine as long as you don't get heavy handed. Make sure to
place a pan underneath to collect filings for refining.
You'd be surprised how fast they build up.

Grinding wheels work, but they do clog and need dressing.
I guess it depends on how heavy handed the person is and
how much work you plan on doing.

Steve Ramsdell

Subject: RE: Will Sanding Silver Hurt My Lapidary Wheels?

I have been doing channel work for over 20 years. Each time
you finish a piece of channel work, you do a lot of grinding
of silver much as the member asking the question describes.

I started out on old fashion corundum wheels, sand paper on
expanding drum and am now using diamond wheels on a Genie.
I have never experienced any problem on any of these wheels
and many times I have gone from doing channel work to
cutting cabochons and have seen no problems on wheels or
polishing buffs in any way.

Hope this helps.


Subject: RE: How to Polish Black Onyx?

Black onyx is usually agate that has been treated or dyed
black. You can polish it like you would any other agate,
but be careful of going too deep.

Today I was very disappointed in a carnelian I planned to
cut. It looked solid red, but when I sliced into it, the
color only went down about 1/8th of an inch.


Subject: RE: Polishing Glass/Obsidian on Vibrating Tumbler

Follow standard methods in tumbling but shorten the time
for each stage considerably.

Polishing requires a lot of cushioning materials. Plastic
pellets are available for this purpose. I have used foam
egg cartons cut into small pieces. Cerium Oxide is probably
the best polish for Obsidian.

Ed Elam

Subject: RE: How to Clean Spots from a Crystal

<<Can someone tell me how to remove silica spots from
crystals? Both inside the tiny cracks and out.>> >>

Just a side comment:

I know there are probably very few people on this list who
use their lapidary skills in conjunction with crystal
healing but there are many crystal healing practitioners
who would welcome the fact that crystals contain silica
spots, rust or any other natural lapidary type flaws.
In the crystal healing world something like that is
generally considered an enhancement for specific spiritual
enlightenment and contains beneficial therapeutic values.
Groups like this would swarm over natural crystals like

Good health to all,

Sandy: My Mom taught me a lot of old sayings, and one of
them fits quite nicely here: One man's mete (or medicine)
is another man's poison! So for you, the flaws may be
medicine (literally) while for lapidarys, they are poison!!
Thanks for the comment. Many people put down crystal
healing, but I think we should live and let live. I don't
have to believe in it, and others may believe anything they
wish. But I don't want to see any discussion of that
difference of opinion here on the digest, as it is outside
the scope of who we are. Thanks hale

Subject: RE: FS: Books on How-to-build Lapidary Equipment

I just bought the set of three books from Mr. Laub on eBay.
They are definitely worth the money.

I plan to get together with some folks and do a rummage
sale scavenger hunt and build our own angle head cabbing
machines. The diagrams are clear and the directions are
well written.

Even those with little experience with tools should be able
to build the machines in the books. I would recommend them
to anyone who would like to try their hand at making their
own equipment.

Giovanna: I hope that when you build that cabbing machine,
or any other machine, you will write up your experiences
and send them in for publication. hale

Subject: WTB: Slab/Trim Saw

I am looking for a 10" or 12" slab/trim saw. I can't afford
to pay new or nearly new prices. If anyone has one to sell,
please contact me at the address shown below.

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