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 259 - Thurs 1/13/2000
2. NEW: Protecting Druzy Quartz from Grit and Polish
3. NEW: Grinding Wheel Bushings
4. NEW: Want Advice on Flat Laps
5. NEW: What and How to Polish with Tin Oxide
6. RE: Risk of Almag Oil Explosion in Sawing
7. RE: Risk of Almag Oil Explosion in Sawing
8. RE: Cutting Material from Israel
9. FS: Sugilite
10. BIO: Stephen


Subject: LapDigest News for Issue No 259 - Thurs 1/13/2000

Ernie Ogren <> wrote that this year's
Quartzsite schedule and show information may be found on
( This years dates have been moved up
to accommodate the Tucson show, so everything will be gone
by Jan 31 except for the Main Event and Clouds Jamboree.

Ernie included an interesting story: "Many years ago before
my first trip to Quartzsite I said to my friend on the phone
that I would see him there and he couldn't stop laughing,
and when I came over the hill from Blythe and saw the
multitude of motorhomes and trailers I then realized why.
It is the greatest sight in the world (from a rockhounds
point of view) and I have not missed a year since."

Ernie, enjoy and have fun at Quartzsite!!

In the last issue, I asked whether any members going to
Tucson or Quartzsite would act as correspondent to the
Digest, and report any news about lapidary rough or
equipment which they saw there. Also, names and addresses
of any dealers with great looking cabbing rough! I still
need those volunteers. If you can do it, please write me.

We have had a couple of volunteers and I appreciate their

My brother is having an eye operation and will be unable to
drive before and for a time after. So I'm going up to the
mountains and help out with driving, shopping, and so on.
Hope to be back by Monday or Tuesday. So the next Digest
should be published on Wednesday.

You guys take care, hug the ones you love, and above all,


ps: To new female subscribers, when I say 'guys', I mean
ALL of you... As used here, 'guys' is NOT gender
specific!! So please don't write!! (smile) hale

Subject: NEW: Protecting Druzy Quartz from Grit and Polish

Hello; I know that when you polish a rock with a little
vug of crystals, it is possible to fill the hole with Fels
Naptha soap and replace it with a fresh plug every time you
change grits.

But what about a larger druzy surface (like the leaves on
this month's Lapidary Journal cover)? How do you protect
something like that to keep the finer grits and polishing
compound from getting wedged into the cracks forever?

A similar problem: I have a clock of mariposite that is
almost finished. Due to a misjudgment on my part, the base
got broken. I am going to flat lap another base for it, but
I would like to leave the edges rough. However, do I keep
the polishing compounds out of the rough edges?


Rose Alene McArthur

Subject: NEW: Grinding Wheel Bushings


I'm looking for information on the dimensions (OD & length)
of bushings used for spacers/bushings between nominal 8"
grinding/sanding/polishing wheels.

My shaft size is 1" OD. Most of the advertised wheels state
the wheel width as 1-1/2" or 2". Would this also be the
thickness at the hubs or would the width at the hubs be
different than the width at the outer edge of the wheel?

Are there also any opinions as to which brand of wheels to
use or avoid?

I have several ideas which include making them out of Delrin
or perhaps just buying some bushings, commercial bronze
bearings look interesting and the price is right.

Any Ideas or comments would be appreciated.


Jeff in Kalamazoo

Subject: NEW: Want Advice on Flat Laps

We are in the market for a flat lap. Many of our stones are
UNDER 1" diameter, while some cabs may be as much as 3 or
4 inches at the longest point.

Judging from what I've read on product descriptions, I
don't think vibratory flat laps will do us a whole lot of

If anyone has advise on what type of small flat laps may be
to our advantage, and your own experiences with different
laps, I'd appreciate hearing from you.

Rock on!

Subject: NEW: What and How to Polish with Tin Oxide

I bought some tin oxide awhile back after a friend told me
its great for everything, but I can't find any info on what
its good for, in my ancient lapidary books. Is this used on
leather or hard felt? Any particular stones its good for?

Thanks in advance


Subject: RE: Risk of Almag Oil Explosion in Sawing

<<Have any of you ever heard of an oil fire in a saw?>>

Yes, in a place I once worked, we had a glass fab shop.
They sawed slabs of glass as a first step in making lenses,
mirror blanks, prisms, and etc. The diamond saw was a
modified surface grinder with a plastic enclosure to keep
the spray in. I think that it had some sort of air
scrubbing system also.

One day there was a loud thud/boom followed by folks and
smoke pouring out of the fab shop. One person was missing
his eyelashes, eyebrows, and some hair. The fire was
contained to the saw and was easily put out. They quickly
switched to a water borne coolant. To be fair, they had
used an oil coolant for some years without incident.

Looking forward:
Alan Shinn

Experience the
beginnings of microscopy.
Make your own replica
of one of Antony van Leeuwenhoek's microscopes.

Subject: RE: Risk of Almag Oil Explosion in Sawing

Al-Mag was specifically designed as a cutting oil for use
with materials which throw off sparks. Al-Mag has a very
high flash point (temperature at which it will burn) - and
I've never heard of it catching fire under any circumstance.

The same cannot be said of the old standby cutting fluids -
kerosene, gasoline, diesel & the like - all of which have
relatively low flash points. A hot spark in a saw full of
kerosene vapor can ruin your whole day (not to mention your
house, your life, and the lives of your family.) This is
the very reason why safe cutting oils (like Al-Mag) were

Peter B. Steiner
TripleRock Lapidary
Buffalo, NY, USA
Pallasite on AOL IM
Pete you're absolutely right!! Let's look at the data.
"Flash point is a measure of the combustibility of the
vapors of a material, and is defined as the lowest
temperature at which the vapor of the material can be
ignited under specified conditions. Flash point is clearly
related to safety, and is measured using ASTM standard
testing procedures."

Flash Points (in deg C) of some materials, and the webpage
source from which the data were taken, are:

Kerosene 44 deg C Mobil AU
47 deg C Mobil USA
Gasoline 39-43 deg C

Diesel fuel oil 60 deg C

Almag 146 deg C Texaco
Pella 136 deg C Shell

Thus you can see that Almag and Pella both have flash
points well above (about 2x-3x) those of kerosene, diesel
fuel oil and gasoline. I included gasoline to show just
how low the flash points of kerosene and oil are - and they
are very close to the flash point of gasoline! hale

Subject: RE: Cutting Material from Israel

To Wally:

There is a lovely stone in Israel called Eilat Stone. I
first saw it in 1963 and bought finished jewelry with Eilat
cabochons. I saw it on later trips also, and visited the
King Solomon Mines from where it comes.

Not having the foresight to purchase unset or rough, I have
been on the prowl for it for many years. In all this time,
I have seen it only once.

The dealer was from New York and imported it from Israel.
Sorry, I have lost contact.

Recently, I have seen online messages indicating there is
no more to be found, and all sold there now as Eilat Stone
is imported from the US. I find that hard to believe, and
question the rationale.

Eilat is a city on the Bay of Aqaba immediately adjacent to
Jordan and Egypt. King Solomon's Mines are located there.
A great side trip.

Teresa: From what I remember, Eilat stone was originally
mined from the Timna copper mines, which were just north of
the northern end of the gulf of Aqaba, in what was then
called EDOM, just south of MOAB. There were two other mines
in the area at Feinan and Punon; these three are commonly
called "King Solomon's mines", and were north of the present
city of Eilat, and thus the name: Eilat stone. This was a
copper bearing stone, and blue-green in color. I understand,
Teresa, that the ore bodies were exhausted long ago, so they
import copper bearing stones to sell as Eilat stones. If I
am wrong, will someone please correct me? Maybe you can tell
us when you return, Wally! hale

Subject: FS: Sugilite

I have cut rough Sugilite for purchasing. If you are
interested, e-mail or telephone me at 910-458-9840.
This Sugilite is ready to cab.

I am located at Carolina Beach NC,

Lee Corey

Subject: BIO: Stephen

I am Stephen. I am 14 and joined this list because I collect
rocks and I thought I might find out something interesting.

I have a cabochon machine that probably still works but I
haven't used it in a while. I am mainly into collecting
rocks, but I like to make things with my cab machine. I am
in the Western Carolina Gem & Mineral Society (WESCAGEM).

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