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. 295 - Sat 5/5/2001
2. NEW: What is MGX Powder?
3. NEW: Tile and Glass Drills
4. RE: What Acid Will Clean Crystals?
5. RE: What Acid Will Clean Crystals?
6. RE: Making Opal Mosaic Cabs
7. RE: Tumbling Cast Metal Parts
8. RE: Tumbling Cast Metal Parts
9. RE: Sphere Preform Cutting Jig
10. RE: Other Lapidary Internet Groups
11. RE: Other Lapidary Internet Groups
12. RE: Other Lapidary Internet Groups
13. RE: Other Lapidary Internet Groups
14. RE: Other Lapidary Internet Groups
15. RE: How Do You Cut an Egg Shape?
16. FS: Gem Business for Sale


Subject: LapDigest News for Issue No. 295 - Sat 5/5/2001

I want to apologize to two unknown authors who sent items
for this issue, and which were accidentally lost by me.

Will be at Wildacres next week and at Myrtle Beach for the
week thereafter, so the next publication date is probably
May 22 or 23. If you want to get it touch with me in the
interim, HA HA HA!!! Eat yer heart out!! (big silly grin!)
Do send your lapidary submissions to the usual address:
and I'll collect them when I return.

Amy O'Connell, a member and a very accomplished jeweler and
lapidary, is showing three new stones this month on her
website: The first is a lavender stone from Africa which
she calls Lavenderine (Lepidolite). The next is an apple
green gem Vesuvianite from California - a beautiful
yellow/green translucent stone. The third are several large
freeform pieces of Septarian from Nevada. Septarian is a
natural concretion of gray clay and brown ironstone filled
with yellow calcite, forming some great bold patterns. I
highly recommend a trip to her site:

Received the following letter from our member Oya Borahan;
"At long last, I put a very humble page about carving a
Sugilite to my web site. I also put some jewellery photos
and a page about synthetic and natural emerald comparison
with photos. If interested, my web site address is: Kind regards from Istanbul"
What I like about this is that she shows how she carved the
Sugilite and then shows how it looks in a finished piece of
jewelry. Way to go, Oya!!!

Take care of yourselves.


Subject: NEW: What is MGX Powder?

Hi Hale,
At a local auction I recently picked up a box with about 10
lbs of white powder with -- MGX -- marked on the outside of
the box. It appears to be polishing powder since it does not
appear to be investment or any other white powder of which I
am aware. (Remember those days when we were blissfully
ignorant that such a statement could bring images of illegal
substances?) I have searched the LD archives and have found
no mention of MGX powder. I would be willing to bet one of
your 2600 readers might have a clue as to what I have here
and how it is best used.

Thanks for your help.

Ken Hoffman

Subject: NEW: Tile and Glass Drills

Has anyone tried the glass drill bits, the ones that drill
tile and glass? What is your experience with these on
glass and on various rocks? They are sold at "Home Depot"?


Subject: RE: What Acid Will Clean Crystals?

Kathy Miling wrote:
<<I bought some crystals from a place in Arkansas and they
still have a brownish mineral deposit on them. ..(snip)..
I also bought some acid ..(snip).. and ... I lost the acid.
..(snip)... what (was) that acid, ..., where do I get it,
how do I mix it and for how long do I simmer the rocks?>>

No doubt a dozen others have told or will tell you the
answer to your question; I have been doing this for years,
and this is how I do it.

The acid is Oxalic Acid. You can get it from most hardware
stores; it's ordinarily used as a wood bleach. It IS
corrosive and toxic. Handle with care. Don't be afraid of
it, just be careful. First put your crystals in a Pyrex (R)
or similar glass container that can be heated safely, and
measure water into the container until the crystals are
covered to a depth of at least an inch. Take the crystals
out and measure the amount of water in the jar. Per pint of
water in the jar, add two heaping Tablespoonsful of Oxalic
Acid; warm the water to dissolve the Acid, then, carefully
add the crystals. Bring to a simmer, (NOT a boil), and
hold it there for about an hour. If the crystals are still
stained after an hour, simmer until they are clean, but not
longer than four hours. If they take longer than that,
more heroic measures are indicated. [Do this out of doors;
the fumes from the simmering acid are quite irritating.]
Let the crystals cool in the acid, (probably overnight),
take them out and wash several times in warm water, and dry
them well.

If they are not clean, go back to the store and buy some
Muriatic Acid. This material IS hazardous! Handle with
rubber gloves, stand upwind when pouring it, and DO NOT HEAT
IT!!!! Put the crystals in the glass or a plastic container,
pour in enough acid just to cover, cover the container, and
leave it for several hours, or until the iron stains are
completely removed. The reason that this is not done as a
first effort is that sometimes quartz crystals are cemented
together with Calcite, and Muriatic acid can cause nice
crystal clusters to come apart into individual crystals.

After the stains are off, take the crystals out of the acid
and wash them several times in warm water, leaving them in
the third or fourth rinse water overnight. (Yes, the acid
WILL penetrate the crystal!)

Disposal: pour the acid into a large bucket containing at
least ten times as much water as the volume of acid you are
going to dispose of, and with considerable headspace. Add
Baking soda a tablespoonful at a time until it doesn't foam
when you add it. Then pour it down the toilet and flush
several times.

That should be all the info you need. There are those who
will tell you to take it to a hazardous waste facility, but
neither a salt solution nor a dilute sodium oxalate solution
can be considered particularly hazardous.

Have fun!


Subject: RE: What Acid Will Clean Crystals?

I rather expect that was oxalic acid. Often you can get it,
or products made with pretty much just that acid, in
hardware stores, for use in removing rust stains.
Concentration isn't important. Add some to water. If it's
working too slow, add more. The length of time to simmer
the crystals is whatever is needed to remove the stains.
Shouldn't be too long... I'd guess an hour would do it, if
the stains are, as usual, limonite/iron oxide/etc. You
won't hurt the crystals, which are almost undoubtedly quartz
(clear/white, right? except for the stains...)

Hope this helps.

Peter Rowe
There were five other replies to this query but they all
said the same thing with varying degrees of detail. I picked
the two that I thought were the best and printed them above.
The other replies were by Jeanne Moen, Jeanette, Grant and
Dave Guin. Alan Silverstein, who put together the file on
tumbling which is in the Archives, also put together a file
of acid cleaning of crystals and submitted it, but it is
much too long to include in an issue. I am looking for a
way to combine all these answers and put them in the
Archives on the 'Net. hale

Subject: RE: Making Opal Mosaic Cabs

Hi. My name is Robin Ballard and I just joined the list. I
will be lurking and learning as much as I can from all of
you knowledgeable people. I am a total newbie at this and
will figure it out as I go. I learned stained glass the
same way.

In that vein, I was just reading Opal Advanced Cutting and
Setting by Paul B. Downing, Ph.D. and he has a whole section
in this book on opal intarsia, inlay and using opal chips to
make triplets by gluing them together, with step-by-step

Hope this helps.

Robin Ballard
Thanks. Robin. Paul Downing taught me to cut opal several
years ago at Wildacres; he is a remarkable cutter!! I have
had a copy of that book since it came out, but had never
read it in detail. I should have!! He describes using chips
to make cabs, in some detail. Another suggestion is to keep
chips of opal, cleaned of matrix, in a small bottle, and
enjoy their flash of color as the bottle is turned. The
bottle is also source of chips for making chip cabochons.
Recommend the book for your reading. hale

Subject: RE: Tumbling Cast Metal Parts

I recently attended the Westec industrial tool show in LA,
where a number of deburring systems were on display. Most
of them were basically scaled-up versions of the sort of
vibratory tumblers used by lapidaries, although instead of
loose grits, most relied on graded series of ceramic or
abrasive/plastic shapes, followed by stainless steel shot,
pins, and saucers, then rouge-charged walnut hulls, etc. I
don't think rotary tumbling works very well for cast parts,
since it is too hard on corners and surface detail, but
vibratory deburring/polishing seems to be standard practice.
Of course, this won't entirely replace the need to grind
away sprue stubs, etc., but it should eliminate some of the
subsequent grinding steps. Listed under vibratory finishing
were several firms that have websites: , ,,, and,,,

Another approach was taken by KMtech Corp., based in
Singapore. They use an electro-chemical approach to attack
burrs without damaging delicate parts as vibratory systems
can do - folding burrs over into holes, mashing fragile
structures, or missing deep pockets. They do custom
deburring (I'm not sure if you have to send your parts to
Singapore for this) as well as sell systems. They don't have
a website but can be reached at or
call their US branch at 978-424-2557.

Andrew Werby - United Artworks
Sculpture, Jewelry, and Other Art Stuff

Subject: RE: Tumbling Cast Metal Parts

Go to the website:

and research their Archives. There has been a lot of
discussion on using tumblers for saving time in metals
preparations - though they were mainly interested in gold
and silver, I imagine the basic information would readily
be adapted for your purposes.

They seemed to be using mostly vibratory tumblers and steel
shot and other commercial media.

Sign up for the digest version of the orchid e-mail list if
you want to receive lots of information on metal working and
an occasional post on Gemstones etc.

Best regards
Robert Lowe
Lowe Associates - Brasil
Gemstones, Rough, Specimens
Tucson February 7 - 12, 2002 - GJX # 205
e-mail <>

Subject: RE: Sphere Preform Cutting Jig

Hi Everyone:

(This is not about a jig, per se, but it is about how to
preform a block for sphere-making.)

To make a cube on your saw you need to make one flat at
least a little bigger then your cube size. Now you can
either make a Fence for your saw or a Vise stop.

After making a cube, I have found that if you make a simple
block with a V in it (out of hard wood of course) you can
easily cut the corners off your cube for a sphere.

Make the block to fit YOUR vise so the bottom of the block
sits on the bottom of your vise and the V is cut at 90° to
it; this really aids in quick line-up.

Always draw the pattern on your cube, so you don't over-cut,
rotate the cube in one direction till those corners are cut
then rotate the other way or confusion WILL set in.

Good luck, and Hale, have fun in Wildacres or

Subject: RE: Other Lapidary Internet Groups


First, there is the daddy of all Internet rock groups:

It is not aimed at a single aspect of rockhounding, but
encompasses them all. It is (or was, I don't know which) the
website for Rock and Gem magazine, and has their cumulative
index of titles of all published articles, in a searchable
form. And so much more!

Then there is the rockhound mail list, which you may access
via the www at:

Another list is the AFMSA Facetor's Mail list, as described
below by Bob Keller.


Subject: RE: Other Lapidary Internet Groups

Here's one with a petrified wood focus. Send a blank email

Our web page is at:


Subject: RE: Other Lapidary Internet Groups

AFMS Faceters List

The AFMS Faceters List hosts discussions pertaining to gem
faceting and design. Hosted by the American Federation of
Mineralogical Societies, I am the current Faceters List
administrator. Our primary focus is as a topical discussion
group for faceters of all skill levels and to help and serve
as an online information resource for beginning faceters and
users of faceting related software such as GemCad. Some of
the world's most accomplished gemstone designers and
competitive faceters are among our list membership, which
currently numbers about 650 faceters. We are presently
serviced by Yahoo! Groups and our list messages and posts
are available online at Yahoo via a bulletin board type web
interface as well as through an email distributed digest.

Beginning faceters and wannabees are welcome! If you are
interested in faceting and not already familiar with us, be
sure and check out our list home page and extensive faceting
related FAQs on the AFMS web site which includes
subscription info, list policies, a collection of gemstone
designs and faceting related articles at:

Bob Keller


Subject: RE: Other Lapidary Internet Groups

Beyond any shadow of a doubt, The best group out there
concerning Lapidary and rock art is the Orchid Digest.

Subject:: leave blank
Body:: subscribe

Dallas Richardson
Amish: Orchid is the mail list for the professional jeweler,
but there is lots on there for the amateur metalsmith,
jeweler, lapidary, and enamelist. hale

Subject: RE: Other Lapidary Internet Groups

Try some of the following e-mail groups

1) Gemking Daily Faceter-Involved with faceting, Lapidary,
etc. Subscriptions and Archives:

2) AFMS Faceters List - Mostly to do with faceting on index
faceting machines

3)Gemstone World List - Deals with Faceting and lapidary

Best regards

Robert Lowe
Lowe Associates - Brasil
Gemstones, Rough, Specimens
Tucson February 7 - 12, 2002 - GJX # 205

Subject: RE: How Do You Cut an Egg Shape?

I too was interested in how egg shapes were cut and polished
so after no answer was posted in the Digest, I consulted the
Archives and found there were seven messages addressing egg
making in the following issues:
Issue #246, msgs 11 & 12-Subject: RE: Egg Making Machine
Issue #260, msg 6 -Subject: NEW: Egg Making Revisited
Issue #261, msgs 13,14,15,16 Subj: RE: Egg Making Revisited

I enjoy using the archives to find information. Thanks to
all who contribute such useful knowledge.

Allan Beane

Subject: FS: Gem Business for Sale

Gem show dealer has to retire after 23 years. Selling total
inventory at cost. Wide variety of cut stones, diamonds,
jewelry, gold, silver, facet rough, beads, pearls, crystal,
specimens, etc. Also have all the supplies and tools for a
complete setup (show cases, lights, electrical, display
items, scales, labeler, trim saw, gem microscope, etc.),
and they are offered at a depreciated price. Perfect for
someone who wants to enter the gem show circuit right away-
-everything necessary to get started. Sold as package deal
only. Priced at $32,980. Complete list available upon

Kathlene R. Maas
E & K Maas Gem Stones
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