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

This list digest contains the following message subjects:

1. LapDigest News for Issue No 253 - Sat 12/11/1999
2. NEW: Cyanoacrylate for Doublets & Triplets
3. NEW: Polishing Emerald Slices
4. NEW: Tumbling Corundum
5. NEW: Marble Making Machine
6. NEW: Need Sphere or Sphere Maker
7. NEW: Easy Marking Pen for Softer Stones
8. RE: Making Large Flat Surfaces
9. RE: Making Large Flat Surfaces
10. RE: How to Apply Cerium Oxide to Leather
11. RE: How to Apply Cerium Oxide to Leather
12. RE: Does Sandstone Crack Opals?
13. RE: Whale Wax?
14. RE: Whale Wax?
15. RE: Whale Wax?
16. Re: Storage of Cutting Materials
17. BIO: Mike Trimble


Subject: LapDigest News for Issue No 253 - Sat 12/11/1999

Please remember to include only one query or response to a
single message. If you need to break it into two e-mails,
then do it! Remember: ONE MESSAGE=ONE TOPIC!!!

Sometime ago we considered the question of whether knapping
should be a topic we would include under lapidary, and by
consensus of responses, decided to include it. Now I want
you to consider a particular type of mosaic... Look at the
work of Jonathon Mandell as an example: and then click on
"ARTcnet_Presents_Jona..". He uses semiprecious stones as
grrist for his mosaic mill. Enjoy!!!

The Victoria Lapidary and Mineral Society's webpages contain
some information of working with Abalone, Amber, Jade, Fire
Agate and Goldstone. Well worth looking at; it is at:

That is about it; take care of yourselves and the ones you
love, and above all, H A V E F U N !!!


Subject: NEW: Cyanoacrylate for Doublets & Triplets

Hi all,

Does anyone have experience using cyanoacrylate in glueing
opal doublets & triplets? What are the advantages and

Hans Durstling
Moncton, Canada

Subject: New: Polishing Emerald Slices

I would like some tips, suggestions etc. on how to
successfully polish Emerald Slices. What Laps, pads, speeds
etc. and what polishing powders and methods are recommended.

Best regards,

Robert P. Lowe Jr.
Lowe Associates - Brasil
Gemstones, Rough, Specimens

Subject: NEW: Tumbling Corundum

I (I mean my son {;)} have run 4 loads through the tumbler
with increasing success, and am accumulating rough from
many sources. Recently picked up a 2 lb. lot of low-grade
"star" corundum, with hopes of tumbling it. From my
readings and archive searches, I gather that a vibratory
tumbler is the preferred method with this material, but
alas I don't have one. In that corundum and silicon
carbide are similar in hardness, I assume I am in for a
rather long series of grinds.

Can anyone provide any helpful hints, secrets or
recommended polishes that may improve my results in a
rotary tumbler?



Subject: NEW: Marble Making Machine

I am interested in purchasing or making a sphere making
machine, but with the intention of making marble sized
spheres. I collect rare marbles and want to add some
"rocks" to my collection. Sizes would be from 1/2" to 1
1/2" diameters.

Bill Hoefer
Hoefers' Gemological Services
Bill: A couple of members of this list only make marbles.
They are Keith and Ann Berger; you may contact Ann at with questions about machines for
marbles. See their link in our Member's Links in Archives.
Also see items on spheres in our Archives.

Subject: NEW: Need Sphere or Sphere Maker


My name is Robert Webb. I am current president of North
Georgia Astronomers and are erecting a Scale Model of Our
Solar System in the public parks of Gainesville, GA. We
are using a 1 : 2,000,000,000 scale. At this scale
Jupiter is 2.8 inches. We thought a banded Mexican Onyx
sphere would be perfect.

While scouting the Web for a source I came across your
article in LapDigest News Issue No. 155 - Sat 7/11/98.
If you could direct me to someone who has some spheres
close to this exact size, or someone who could make some I
would appreciate it.

We also need extremely small spheres, some 3.5mm spheres
of pink marble for Mars.

Thanks for your help,
I thought some of you might be able to help him. Please
communicate directly with him, but copy me (not for
publication) at Tks hale

Easy Marking Pen for Softer Stones

I have found an easy marking pencil for the softer material.
It's somewhat waterproof and can be rubbed off with some
paper towel and a little pressure. The pencils are made by
Dixon and they can be found in any office supply store.
Called a film marking pen, they are used to mark notations
on X-Ray films by the Radiologists. I'm a X-Ray Technologist
but a rock hound just the same.

This Journal is the best thing since Chicken soup for the
Novice Stone worker. Keep it up,

Dave Garner

Subject: RE: Making Large Flat Surfaces

To Brad Smith, there is a new way to easily sand and polish
large surfaces, flat and/or curved, concave. It is hand
held and has a variety of heads; it works incredibly fast.
I have seen it the last two years at Camp Paradise in the
hands of Cal Clason of Kern County Minerals.

Contact Cal via his wife Dee <> I have
forgotten the manufacturer.


Subject: RE: Making Large Flat Surfaces


Amateur and professional astronomers polish glass (Pyrex)
mirrors and flats to produce the optical surfaces needed
for their work. While this is traditionally done by hand,
working a glass tool against the mirror, many clever
machines have been designed to accomplish this work (and
the machines are used for all larger objects). The same
machines can be used for polishing large flat surfaces of

Go to your Library and find a copy of Amateur Telescope
Making (a three volume set) edited by Albert Ingalls and
published by Scientific American (various editions from the
1920's to the 1960's). It will provide you with details of
several polishing machines, such as the Hindle, that you
can build yourself. Most of the machines covered were
designed for 10 - 20 inch surfaces and should meet your

Kreigh Tomaszewski
Please visit our family web pages at

Subject: RE: How to Apply Cerium Oxide to Leather

<<The corrected formula is, one 4 oz. bar of Ivory Soap,
cut into shavings, one pound of oxide, and two cups of
water. Heat slowly until it reaches a thick cream

Instead of using soap why can't one use car wax or
something like that? What is special about using soap?

Kind regards from Istanbul

Oya Borahan

Subject: RE: How to Apply Cerium Oxide to Leather

About the time we started the Digest, I asked the same
query and received a number of replies. I just found that
file and am reproducing it below to get it into the

The old file starts.....

"I use a Pixie for cabbing, and I want to get other's ideas
for the best way to apply cerium oxide to the polishing
disk on the end of the Pixie .... How do YOU apply it?

Hale Sweeny
I don't have a Pixie, I have a Richardson's buffer, but
the answer is, I don't apply it to the disk. I use a
spray bottle to wet the disk as it spins, and also to
wet the rock. Dip the rock into a little tub of dry
compound so it picks up some powder. Smear it around
by finger, also using some of the fluid that drips off
the disk to form a puddle of "mud". (I cover the area
under the wheel to keep it "pure" and clean when not
in use.) Slowly touch the rock to the disk so the disk
picks up the compound. Works for me.

Alan Silverstein <>
Wow, what a lot of work. I use a corn cob buttering
brush and cerium in a cup of water (mix it thin, like
milk), just start the wheel up, wet it down, smear the
cerium on it with the brush, and go for it. When the
wheel gets gummy with used cerium (which will happen, no
matter what you do), just scrape it with the back of a
hacksaw blade while it's runnung (Richardson's
recommended cleaning method).

I know you don't want to hear this but don't do it. If
you must, glue a leather pad on the disk to polish with
cerium. In general, the Pixie rotates way too fast to
get a good polish with cerium. I'd use the diamond
compound that came with the machine.

Tim Fisher <>
If the disk is new, it works best to apply a coat of
polishing compound (cerium oxide, tin oxide, whatever)
over the entire surface of the disk with a narrow (1/2
to 1 inch) paint brush. Put the compound in a plastic
container and add water until a soupy mixture forms---
apply the oxide from this. Once the oxide is applied,
I keep it recharged by painting over the stone to be
polished with a coating of oxide from the slurry. If the
stone has been properly sanded, that should be enough
compound to finish the stone.

Hope that helps.

Roger Pabian <>
Get a 12" polishing wheel from Richardson's Ranch. It is
the best way to go. They have their own motor and will
put a mirror finish on your material. Their phone is
1-800-433-2680. The cost is 195$ plus shipping. Norma
will have it shipped that same day.

Tell Norma Terry said "Hi".
Terry Ensell & Julene Kanies <>
> Wow, what a lot of work.

?? It's easier than it sounds, I guess. I just "butter"
the rock with some polish compound now and then (using my
fingers). No need to brush the wheel (or waste compound
in the process), though of course I did coat it well when
it was new and I first turned it on. (And I keep it
covered with a plastic shower cap when not in use.)

> When the wheel gets gummy with used cerium (which will
happen, no matter what you do)...

It does? I haven't had that problem. :-)

Maybe because I'm NOT brushing on the compound liberally?
I lose enough to sharp edges (on rocks) while polishing,
I guess. A little cerium seems to last a LOOONG time
this way.

Alan Silverstein <>
By the way, does anyone know if cerium oxide is
dangerous? Toxic, radioactive, causes sterility, warts,
body odor, ... :-)

Alan Silverstein <>

Make up a paste. Moisten the pad with a squirt bottle
of water. Then, using a toothbrush, apply the paste.
Continual applications are necessary. Alternate between
the paste and the water to keep a moist pad.

Ken Flood (Keweenaw Gem & Gift)
Hi Hale - and fellow subscribers

I use a Graves cab mate. The polishing disk I use is a
homemade one that screws into the shaft, 6 inches in
diametre, and has leather glued to it, skin side (smooth
side) out. I keep a cerium oxide and water slurry in a
plastic jar (the kind bicycle riders drink water from)
which has a pressure fit lid with a hole in it. Into
this hole I forced an artist's paint brush. When needed
I shake the jar and paint the slurry on the wheel. A
little goes a long way this way, and it keeps
contamination out. (H. Durstling)
Hi Hale,
I have a Genie and I apply cerium oxide or whatever onto
the leather polishing disk with a small sponge rubber
paint brush that you can pick up in any hardware store.
It is simply a 2 inch square piece of sponge rubber stuck
on a stick. Dip it into a slurry of cerium oxide and
paint your polishing disk. Turn on the machine and zip,
you'll have a beautiful polished stone in no time at all.

Ron West <>
I was taught to use an old dish detergent bottle. Just
keep a slurry of cerium oxide in the bottle and shake it
to put it into suspension before you squeeze a little
onto the leather disk. (Makes a real mess if the disk is
rotating at the time!) I use a polishing disk mounted on
the end of the unit rather than a belt.

"LECHNER, KAREN" <101600.2063@CompuServe.COM>
I use 2 methods, first (most often) a small brush dipped
into the slurry, then applied to the pad.

second (frequently) dip the stone in the slurry and apply
to the pad. Either way is messy but effective. One
caution, don't allow the pad to become too dry (excessive

"Earl English" <>
<<I use a Graves cab mate. The polishing disk I use is a
homemade one that screws into the shaft, 6 inches in
diameter, and has leather glued to it, skin side (smooth
side) out.>>

Rough side out seems to work better, especially if you
"rough it up" by rubbing it against the grain with the
back of a hacksaw blade after each use.

<<Make up a paste. Moisten the pad with a squirt bottle
of water. Then, using a toothbrush, apply the paste.
Continual applications are necessary. Alternate between
the >paste and the water to keep a moist pad.>>

This will waste a lot of cerium, which at $16/lb. or so,
is a lot of money too. Make it really thin, like milk.
Optical cerium (don't get the regular stuff, it stinks!)
goes a long, long way. I am not yet through my first
pound and I've been using it for 2 years.

Tim Fisher <>
<<If you must, glue a leather pad on the disk to polish
w/ cerium. In general, the Pixie rotates way too fast
to get a good polish with cerium. >>

Please define "too fast". I have been using cerium oxide
on an 8x3 drum with a leather belt running at 1150 RPM.
The results have been less than stunning!
I have a Titan and a Pixie and I've never been too happy
with the disk for polishing. I ended up buying a real
old faceting machine for fifty bucks, a floor model, and
I use a full grain leather disk I cut from scrap on that.
The nice thing is that since it lays down the Cer/ox and
tin/ox slurry impregnates better. I've actually found
that a little tin oxide mixed with the cerium helps on
quartzes. One thing I have found is that the leather
can tend to glaze or get foreign material on it from
time to time. When I does, a sharp paint scraper takes
care of that.

"Derek Levin" <>"

With the recent answers. I believe this about covers most
of the ways of applying Cerium oxide to a leather disk.


Subject: RE: Does Sandstone Crack Opals?

Kreigh wrote:

<<Potch (sandstone) on the back of an opal breaks the
surface and leads to molecular stress and eventual cracks.
I thought this was common knowledge.>>

Interesting information. I would assume it's not common
knowledge, since it doesn't appear in Downing, and (in
personal emails to me) a few cutters with well over 50 years
of experience between them say sandstone does not increase
breakage. I would say that it's not immediately evident to
me that potch necessarily breaks the surface structure of
the stone. It could form on the surface after the opal
does, and just be layered there. I imagine the surface at
a molecular level to be a chaotic place, with a junction
between sand and potch that is not at all flat and level.
Let's face it: the only surfaces that are straight and level
at the molecular level are crystals, which opal isn't.

That's not to say that that you're not right.

But, while a top, gem-grade opal with a polished back is
good, there seems to be many, many opals that don't have a
polished back for every one that does.

I've personally read:

1 - always polish the back
2 - it doesn't matter
3 - never polish the back of a crystal opal, because it
makes it easier for light to get out of the stone.
4 - polish the back of a crystal opal because it makes it
prettier - especially if it's a big stone that won't
get a bezel backing.

Downing's input on this matter is that lack of polish or
defects on the back do not affect the value of an opal,
while cracks make the stone worthless.

In these days of a seeming shortage of gem grade opal,
stones are being accepted with things that would have been
considered faults years ago, as long as they are pretty
stones. The few jewelers that I have spoken with had no
preference for a polished back, or a back free of

If I may be permitted to go into my "engineer mode" (sorry,
it's what I do), we need a real study here. It's likely to
take years, and to be adequately controlled would involve
cutting and observing stones from a variety of fields with
and without sandstone on the back. As with all studies, if
one study claims a link and others don't, a reasonable
conclusion might be that if there is a link, it isn't
particularly strong.

This is the way I understand things. Of course, I reserve
the right to be wrong. I just want to understand these

All the best,

(If you know me, you may want to note my new address!)
Bob Lombardi W4ATM in Melbourne, FL (ex-WB4EHS) or or

Subject: RE: Whale Wax?

Hail Hale,

Always wanted to say that, but I suppose you're tired of it.

Here's an email response to my whale wax query from Michael
at metalwerx. He said it would be OK to forward it to the

"Chunk, The Griegers whale wax is a synthetic wax made to
resemble the real whale wax. Lapidary people would use it
to enhance the color of stones. I use it to bring out the
color of rough Lapis which I use in jewelry. It is listed
for use for number of similar soft stones, turquoise etc.
The way to use it is to gently heat up the wax until it is
liquid. You never need very much as a little bit goes a
long way. If you have a hot plate that would work great."

"I put the wax and the stones on the hot plate and turn on
the hot plate to about 150 degrees. I use a paint brush to
put the wax onto the stone. If the wax turns opaque the
stone is not hot enough. Once the stone is up to
temperature the wax will remain liquid. I then let the
stones sit on the hot plate for a while to let the wax
soak in 10-15 minutes should be enough. I then remove the
stones and wipe the excess wax away. I then let the stones
cool and come back and buff them just as if you shining
your shoes. Maybe this is more than you were looking for
but what the heck."

"Michael at"

Chunk, only if you add: "The Gang's All Here"!!! hale

Subject: RE: Whale Wax?

Regarding "Whale Wax" by Griegers. I do not know if it is
from whales or not, but I doubt it and I used it over 25
years ago, and have never seen it since. I warmed it until
it was liquid and placed a soapstone sphere in it and left
it for about 10 minutes. It brought the color out to a
great finish and did not polish it after, being careful not
to create a rough area when it dries and the excess comes
off, turn it as it cools.

Subject: RE: Whale Wax?

But what types of stones do you use it with? Or, more to
the point, what stones (names) does one use that wax on? Do
you use it on stones which can't take a good polish? Or, do
you use it on stones which are soft and permeable so that
the wax is taken into the interstices of the stone?

Why did people stop using it? Is there a better substitute?

Are there any wax substitutes available today that one may
use? Chunk, what wax does Michael use today? From what was
said above, we would need a wax which melted below 150
degrees F.

Can anyone give us any help here?


Subject: Re: Storage of Cutting Materials

Thanks all for your suggestions on storing rocks. Here's one
sent to me by Kieth Ludemann off list. I thought it was a
good one and asked his permission to share it with the
group. Here it is:

"I have shelves from Boeing Surplus which are eight ft.
high and 3 ft. long and 18 inches deep that will support
500lbs per shelf. The first shelf is set 12" off the floor,
then shelves every 12", with the top one 12" from the
ceiling. I built a box of 1/2" plywood that is 11-1/2"
tall by 18" deep by 11-3/4" wide, so that 3 will fit on a
shelf. My shelves are nine boxes high; with 3 on a shelf, I
can get 27 boxes to a shelf section. I slide them out to
get at the material, or you can make the front shorter so
you can see or reach in."

Thanks again

Steve Swartz
Carson City, Nevada USA

Subject: BIO: Mike Trimble

Hi all. I am a civil engineer in St. Louis with a strong
interest in mining and geology. I first became acquainted
with rocks and minerals while a child, due to regular trips
to the Denver show. Became a serious rockhound in college.
Was always interested in lapidary work, but never pursued

My 8 year old son recently received a toy rock tumbler for
a birthday present, and Dad has been going hog-wild ever
since! (Am hoping Santa will bring a nice new Lortone
model for Christmas!).


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