Edited and Published by Hale Sweeny
Web Site: http://www.lapidarydigest.com
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. 297 - Sun 5/20/2001
2. NEW: Wildacres Report
3. NEW: Aqua Aura
4. NEW: Datolite, a Lapidary Material
5. NEW: How to Dop a Piece of Topaz
6. NEW: Polishes to use with Different Stones
7. RE: Sphere Preform Cutting Jig
8. RE: Sphere Preform Cutting Jig
9. Re: Tumbler Noise
10. RE: Tumbler Noise
11. RE: Tumbler Noise
12. RE: Tumbler Noise
13. RE: What is MGX Powder?
14. RE: Trip Report from Aussie Opal Country
15. RE: What Acid Will Clean Crystals?
16. FS: Lapidary Rough, Wholesale
Subject: LapDigest News for Issue No. 297 - Sun 5/20/2001
The Digest received the following letter:
"Thank you very much to Hale, The Lapidary Digest, and to
everyone who responded to my inquiry about my Hillquist saw.
You were right on and I have contacted them and found the
solution to my problem. I have ordered a kit for $85 which
will upgrade my drive to a newer style that will improve my
older saw. This is the only place that was able to answer
my question correctly. Others told me that Hillquist was
out of business and that there was no way to fix (it).
Thanks again Hale and everyone. A grateful subscriber."
It wasn't me, it was you who send in the answers which
solved his problem. Letters like this show that your
participation is what makes the Digest work.
Are there any areas of lapidary you would like to read more
about? If so, lemme know.
Subject: NEW: Wildacres Report
(Since I didn't go, I asked Ed Elam, for whom I was supposed
to help teach channel work, for a little report, so you
could see what I missed! Here it is.)
Sorry Hale did not make it to Wildacres. Wildacres is an
experience not to be missed. The guest speaker this session
was Bob Jones, Senior Consulting Editor of "Rock and Gem"
magazine. His presentations were very interesting and Bob is
a delightful speaker. His wife, Carol was with him and she
is a fine artist in her own right. I always enjoy the
chance to talk to Bob and Carol and to the other speakers
who come to EFMLS Wildacres.
"Show and Tell" night produces a wide array of projects
completed by the students during the week. And, yes Hale,
all seven of my students produced an acceptable piece of
Two areas of the Wildacres experience not often mentioned
is the tail-gating and the auction. This was of particular
interest to me this year because I was able to acquired
some specimens for my collection. During our visit to the
98 National Show at Houghton Michigan, I became intrigued
by the cut and polished nodules of porcelaneous Datolite
which are found in various copper mines of the Upper
Peninsula. Those I saw at the show seemed a bit pricy so I
passed them by. At the tail-gating at Wildacres, one of the
participants had a nice assortment of Datolite nodules at
reasonable prices. I bought one from him, a rose pink
nodule about 4.8 centimeters.
An auction of donated material to help cover expenses is
held the last night of each session. The gentleman with the
Datolite nodules put two in the auction. I also bought one
of those, a white nodule showing fine gray crystals in the
face of the nodule. I also bought some very nice Lake
Superior agates donated by the same person. As fate would
have it, this person liked the Channel Work Bola that I put
in the auction so he bought it!
I consider myself very fortunate to have been able to attend
the EFMLS and the SFMS sessions at Wildacres many times.
Subject: NEW: Aqua Aura
Do you or any of the digest readers know how to make aqua
aura from quartz? I've seen it at some rock shows and one
seller said that it's made by plating quartz with 24K gold,
but that doesn't sound quite right to me. It must be bonded
somehow, but I'm not sure how.
Subject: NEW: Datolite, a Lapidary Material
My friend Ed Elam told me about a mineral he bought at Wild-
acres named Datolite, from the upper peninsular area of
Michigan. Since it is described as a lapidary material, I
abstracted the following information for the Digest:
Color: Colorless, white, pale yellowish, pale greenish,
pinkish, reddish, brownish
Opacity: Transparent to translucent
Hardness: 5 to 5.5
Density: 2.8 to 3.00
Fracture: Conchoidal to uneven; brittle
Habit: Crystals short prismatic; granular or porcelaneous
(Source: Mineral Database)
As one example of a lapidary use of this material, Robert
Smith, in "Scrimshaw: An Important Facet of the Lapidary
Hobby", published in Eclectic Lapidary, Vol.1, No. 10 dated
09/01/97, notes that: "Some enterprising artists in
Michigan's Upper Peninsula make excellent scrimshaw using
polished slabs of the mineral "Datolite". This is sometimes
found in small nodules in the dumps of the old copper
Datolite from copper country of northern Michigan occurs in
two distinct forms: as porcellaneous nodules (which is what
Ed bought) and as vitreous crystals. The nodules have an
outer surface which looks like cauliflower, and is the
massive form of interest to lapidarys. The mineral ranges
in color from white to gray, brown, red, orange, yellow and
green. I have been told that the porcellaneous form only
occurs in Michigan copper country. If bought from mineral
dealers, it is very costly to use as a lapidary material;
the only practical way would seem to be as a self collected
Polish with tin oxide.
Some web references are:
The website of Keweenaw Gem & Gift Shop in Houghton, MI,
showing pictures of Datolite and other UP minerals of
interest to lapidarys. Run by Ken Flood, a nice guy.
Other references are given below; add http:// to the start
of each reference:
Subject: NEW: How to Dop a Piece of Topaz
I have a nice big piece of Topaz I want to facet. I have
been told to dop it 5-10 degrees off one of the cleavage
planes or it won't polish. The piece is triangular in shape
(water-worn); how do I dop it ?
I want to maximize the yield, and if I off-center the dop,
I lose using the biggest flat surface for the crown. It is
shaped like one of those old colonial three-pointed hats.
This is slightly outside the scope of items we usually put
in the Digest, so I am asking if you have an idea of how to
dop this piece, please write to Hilton directly. hale
Subject: NEW: Polishes to use with Different Stones
Wondering which polish to use with that stone? Wonder no
more. Polishes to use with different stones are listed in
the following website:
Subject: RE: Sphere Preform Cutting Jig
The formula for the distance from the edge of the cube to
the blade is: distance = (cube edge length)*1.207
Ore-ROCK-On Rockhounding Web Site
Subject: RE: Sphere Preform Cutting Jig
How about trying this? Get a concrete coring drill of the
appropriate diameter. Do three cuts on the each axis
(X,Y,Z). Then do two more cuts, one at the 45 degree angle
between the positive X and Y and Z axis and one between the
negative X and positive Y and positive Z axis. You should
end up with a really good preform!
The problem is developing a method of holding the rough for
the last three cuts. Maybe a transfer jig like they use in
Subject: Re: Tumbler Noise
I've built a number of sound proofing chambers, including
several for tumblers. The easiest way I know to construct a
sound proofing chamber for a smallish machine is to go to a
department or hardware store and find a plastic container
big enough to hold the device with about 6 inches of room to
spare all around. In the US these containers are very easy
to find at K-Mart, Wal-Mart, Target, etc. I've even used
plastic trash barrels.
Cut a piece of plywood to fit the bottom of the container
and hot-glue a piece of 6 inch open cell foam to it. Put
the plywood in the container foam side down. This gives the
machine a stable base and will cut down on the vibration
that is transmitted through the bottom of the container.
You can often get good sized chunks of foam for little or
no cost at fabric stores or any place that does upholstery.
For the interior walls and lid you can either hot-glue
egg-shell foam or again use 6 inch solid foam. You can cut
a small hole in a corner to run the power cord through. One
you snap the lid of the container on (another advantage of
using an off-the-shelf container solution is that the lid
fits perfectly) the noise coming from the machine will be
The real problem for this type of container is the heat
buildup. When I built them in the past, I didn't want to
take the chance that the heat buildup in the container would
reduce the motor life. To some extent I resolved the problem
by buying a 3 inch computer fan at an electronics "junk"
shop. These fans are cheap, move quite a bit of air, and
last forever. You can easily hook them up to a cheap power
supply. I cut a hole in the side of the container and the
foam to mount the fan and another hole in the opposite side
to serve as an air input.
The good news is that the fan prevents heat from building
up in the container. The bad news is that even a small hole
in such a container degrades its soundproofing ability.
However, life is not perfect and this type of container
should be good enough to prevent your neighbors from
mustering the pitchforks and torches.
Subject: RE: Tumbler Noise
Back in the 'old' days before ink jet printers, impact
printers were pretty loud. Most businesses put their
printers in nicely built soundproofed cabinets. I got one
for free from a used office furniture store. It is very
solid with egg carton foam and has a hinged Plexiglas lid
that lets me easily reach in and check the barrels. It also
has a built in exhaust fan. I did add a couple pieces of
scrap carpeting to set the tumbler on because I thought the
vibration may tear up the foam on the floor of the cabinet.
Subject: RE: Tumbler Noise
I had a problem with motor noise on my 15 pound Thumler
tumbler and I did two things. One was to put it on soft
wood on the floor. Then put a heavy cardboard box over it.
It works great, its cheap and so far the motor has not
complained. Most of the modern motors have overload
protection which will kick in if they get too hot (it
never has). I oiled the bearings but that didn't help with
the noise, but the cardboard box did the trick. I got one
of the heavy duty parts shipping boxes here at work and cut
the flaps off so it would sit down flat on the floor.
Best of luck with it
Subject: RE: Tumbler Noise
Small Parts <www.smallparts.com>, sells a variety of noise
and vibration-dampening materials suitable for placing
under machinery or for building noise-dampening enclosures.
Their catalog contains an amazing array of fasteners, tools,
metal shapes, and neat gizmos suitable for the tinkerer or
Subject: RE: What is MGX Powder?
In response to Ken Hoffman's query, MGX is a polish powder
originally named by Mr. Gold who at one time owned Gem-Tech.
Contempo Lapidary acquired the name and continued to sell
it as MGX. It is an Aluminum Oxide material with a micron
range of 0.5-4.0, and is very similar to "Lusterite I"
I have used it for just about everything. It is excellent
for all quartz based materials and I found it worked
extremely well for marble and granite also. I used it on
both when I did my bathroom and kitchen with those
materials. I did not care for it as much as cerium oxide
on opal. Maybe for a pre-polish on opal.
I believe Ken unknowingly made a good buy when he got it.
Now I am just curious as to who went out of business and
had that much of the material.
Subject: RE: Trip Report from Aussie Opal Country
Well, it's almost over. Arrived in Sydney today for 2 days,
then back to LA and Chicago. We had to buy another suitcase
to carry all the rough we mined in Yowah and Lightening
Ridge. The Ridge was fabulous!!! We actually did get down
into a working mine, saw some seam opal and nobbies I would
have killed to have but, alas, had to content myself with a
few pieces of seam specked off the backstow piles and a
gorgeous bottle of huge lightening ridge rough I bought off
some miners straight from the field we visited in Growen and
Glengarry. These are two places actively mining, right now,
almost a "rush" with jackhammers screaming, picks, loaders,
excavators. It was incredible. And, if any of you have heard
of Len Cram, who writes those incredible opal books, we got
to spend the day with him and hear his stories of his times
in the mines, what it was like 40 years ago, his theories
on the creation of opal. It was awesome! Have nearly 20
floppies to go through to download all my pictures and go
We'll just be tourists for the rest of the trip, but have
gone into opal shops with newfound knowledge. It's really
sad that the miners have to sell their rough and cut stones
for so little, only to see the stones in Sydney marked up
hundreds of times. Wow.
I'm going to get about 2 hours of material together with
pictures and samples. Then, if any club or group is willing
to pay my traveling expenses and work around my schedule,
I'll be glad to come down, up or over and share my 3 week
Subject: RE: What Acid Will Clean Crystals?
I have seen it a dozen times, and first laugh at the mis-
conceptions that people can build up out of true but
incomplete information, and then groan at the perpetuation
of a myth. Here is the total truth of the matter.
The ONLY common acid of which the "Never add water to Acid
because it might explode" statement is true is CONCENTRATED
SULFURIC ACID! You can add water to Muriatic or Nitric or
Acetic acids all day, and nothing will happen unless you
are careless enough to splash.
Since Oxalic acid is a solid, you would be spooning it into
water anyway, and the dissolution is endothermic (the liquid
gets cooler). Some Anhydrous solid acids, notably Phosphorus
Pentoxide or Pentachloride liberate a lot o heat in contact
with water, and should be added to water very slowly with
time between additions for the solution to cool, and fuming
Sulfuric Acid and water are deadly enemies and should be
mixed only by a knowledgeable chemist in a well-equipped
But these exotic items are probably not in a rockhound's
closet anyway. HOWEVER the well-used adage still applies:
"If you don't know what you're doing, DON'T DO IT!!"
Subject: FS: Lapidary Rough, Wholesale
For sale - 26.5 tons of selected cutting materials; the
rough rock stock of Small Wonders Lapidary. The material is
stored inside, inventoried, crated, on pallets in rural
Trumansburg, NY. Asking price is $25,000; offers considered.
If interested, please contact Jim Small at 607-532-4155 or
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