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. 214 - Mon 6/21/99
2. Comment: Welcome to the new guys!
3. NEW: Large Scale Rock Tumbling
4. NEW: Chrysoprase Table Tops
5. NEW: Learning Intarsia from Kaufmann
6. NEW: Cutting and Polishing Peridot Cabs
7. NEW: Sphere Making Motors?
8. NEW: Blue Opal & other Cutables
9. RE: High Speed Engravers for Lapidary Work
10. RE: High Speed Engravers for Lapidary Work
11. RE: High Speed Engravers for Lapidary Work
12. RE: Searching for Nephrite Headstone
13. RE: Corundum- Cutting and Shaping Ruby/Sapphire
14. WTB: Cutting of Rocks with a Large Saw
15. BIO: Keith Cheadle
16. BIO: Robert Redden


Subject: LapDigest News for Issue No. 214 - Mon 6/21/99

I may have missed some messages sent on Thursday soon after
Issue 213 was sent out; I was doing some maintenance and
may have screwed-up!

Going to update the member's web pages section of the LD
website soon. (The website is at
If your webpage is are not listed there, please send me a
three or four line description of your website (it doesn't
have to be lapidary oriented) and your URL and I will add
it the Member's Links.

The Registrar at SFMS Wildacres sent a message saying that
there are several openings for the next two Sessions:
August Session : Bead Design(1), Mineral Identification(3),
and Beginning Wirecraft(1). September Session: Gem
Identification(3), Advanced Silversmithing(2) and Advanced
Faceting(2 possible). If you are interested, e-mail Ron and
Anna Denton at These are 5-day workshops
and the total cost for room, board and tuition (except
materials costs) is $225 per week. Ya cant live that cheap!!

I remind our members that the main purpose of this list is
to help members in learning the various lapidary procedures
and techniques, and helping them with problems in design and
construction of lapidary items. So we advertise lapidary
schools, lapidary machinery for sale, rough for sale, and so
on, but not items about rockhounding, collecting or sales of
finished lapidary items. There are a number of other lists
and auction sites much more appropriate to these.

As the ol' timers know, I am very interested in "how-to-make
home-made" lapidary equipment, and want to add drawings
of such to the website. To see the kind of equipment I mean,
look at Andy Parker's website: . He has made
and uses - tumbler, saw/grinder combo, and sander. Anyone
who would like to help with the project by making working
construction drawings or sketches of such equipment? If so,
write me! I hope to have a full section on the webpage
devoted to making your own equipment, and those drawings
would be a vital part.

Hope all is going well with all of you. Take care of
yourselves. Hope all you fathers had a nice Father's Day and
that all of you others - HAVE FUN!!! (smile)


Subject: Comment: Welcome to the new guys!

Hi, all you new members!

You have lucked on to one of the best lists around!! The
people are friendly and willing to answer any "dumb"
questions. I know 'cause I have asked some of the
"dumbest" ones.

Really, they never make you feel like the new guy, or treat
you with anything but respect, and that is a rare thing.
So ask away, and enjoy this list!

< >

Subject: NEW: Large Scale Rock Tumbling

Hi everybody,

I participate in craft shows on a regular basis to sell
my work. One of the frequent requests is for large amounts
of tumbled stones for flower pots, gardens and similar
applications, hence my brainstorm.

The 'storm' - - I was planning on purchasing a cement
mixer, lining the interior with 1/4" rubber and using it as
a large scale tumbler. In Michigan, we have a large
quantity of stone available from 1/4" diameter up to about
12". The larger stones would be too big, however I think I
could probably do stones up to about 4".

I would like some feedback if anyone has tried it or
whether or not they think it will work.


Frederick Warn
Fred: I think the first question concerns the large tumbled
stones which are already 'out there' for these purposes, and
what they sell for. I have bought such stones to place
around the base of my home (about 2" - 4" diameter and all
white and nicely and smoothly rounded), as an architectural
treatment, and they were not too costly. My next door
neighbor runs a company called The Rock Shop in which he
sells all sorts of loose rocks for construction and for
architectural treatment; I'll bet there are several such
companies close to you which can give you some pricing
information. Then go from there! Also check wholesale
Florist's supplies; they may also have them. hale

Subject: NEW: Chrysoprase Table Tops

(In recent issues of the Digest, we discussed jade and jade
table tops and jade headstones; in a footnote to a letter
from Craig about that thread, I jokingly said that he should
make table tops from the large pieces of the Chrysoprase from
his mines! This is his wonderful and serious reply!)

Dear Hale,

How very right you are to say it would be a delight to have
a chrysoprase table. I am sure it is a dream many of us
(please read that as me included !) share.

The possibilities of doing this are raised with me on a
regular basis by people from all walks of life. In
particular, I am often asked if we produce back lit tables,
statues with internal lighting or " stained glass" style
panels. We don't, but if any one does, I would love to hear
from them.

And just as often, I hear argument that no one would ever
find pieces of chrysoprase large enough to produce such
products. So as a matter which I hope will be of interest
to subscribers, I have put together a few notes on the myths
and realities as best I know them.

Historic literature quotes only one source that I have been
able to find of anyone claiming to have seen a chrysoprase
table. Circa 1838 a Dr L. Feuchtwanger describes two tables
in the palace of Fredrick the Great - " Sans Souci " - as
being made from plates of chrysoprase two feet wide, three
feet long and two inches thick. I am not aware of there
being any corroborating reports of the existence of these
tables. However I can say if ever they appear out of some
hidden vault or private collection, I for one would like to
see them. I guess they would be a spectacular sight if they
still exist.

>From my own experience in the industry, I can quite
confidently say that it is possible to find pieces of
chrysoprase large enough to make two tables this size.
Having said that, I am presuming they used a 4"- 5" slab
split down the centre to make the two tables. It is not out
of the question to find one slab that big, but to find two
to match would require a very rich deposit.

The largest pieces of " chrysoprase " I have personally seen
are the chrysoprase skinned nodule or boulder materials.
These can be as big as a small motor vehicle. At this time
these boulders are not in production. They are actually only
a thin skin of chrysoprase over a centre of nickelian
magnesite. As such, massive though some of them have been,
they cannot be used to produce a real chrysoprase table.
(They can produce beautiful tiles and slabs of composite
material using the magnesite centre and a chrysoprase rind,
but that is a matter for a separate discussion another day).

With respect to pieces of actual solid chrysoprase of a size
and grade sufficient to warrant being made into palace
tables, in ten years of looking I have only seen one such
piece - or more accurately parts of one such piece. It came
from one of the mines we now own - regrettably before our
proprietorship. At the time I was acting as a consultant to
an intending buyer and by the time we saw the piece it had
been severely assaulted by a bulldozer ( to " make it small
enough to lift into the truck " the operator at the time
told me later ) and the original size of the piece was
difficult to estimate - maybe a centre of solid material
10' x 10' x 6''- 8" or more ? with a similar perimeter of
less structurally sound pieces - certainly big enough to
have generated two tables of the size attributed to the
Sans Souci collection.

Absolutely AAA all the way through? I wish ! Not at all.
It was a truly spectacular emerald green colour but had
drusy lenses and vugues, shatter lines and so on which would
have made for a great table top but limited its capacity to
produce, say, flawless jewellery. Some big pockets of
flawless material within the piece to be sure but not all
perfect by any stretch of the imagination.

And the chances of another such piece being seen on the
world market ? I would think very good. We, ourselves, have
the appropriate geological environment for further such
finds. Equally, as an off-shoot of on-going nickel
exploration by local companies, the science of understanding
of the formation of chrysoprase and many related minerals
(a few of which are of interest to the lapidary - gaspeite
and the related siliceous nickeliferous magnesium carbonates
- magnesite, citron, lime prase - being the most obvious) is
fast growing both in theory and in application. The better
the science of discovery, the better the chance of discovery.

And this time, if another piece of these dimensions does
turn up, let us all hope it ends up it ends up as a work
of art for all to enjoy. One hopes the next specimen of that
nature will find its way to the Smithsonian or some other
safe haven, rather than ending up as fodder for the cutting
factory floor as did the last one.

And the myth ? We have been plagued for years with stories
of the person who knows the person who knows the Prince of
Saudi Arabia who in turn wants to line his swimming pool
with chrysoprase. Expense is never a problem but cheques
are never seen !

Best wishes to all,

Craig White
Chrysoprase Mines of Australia

Subject: NEW: Learning Intarsia from Kaufmann

Hi Everybody,

I really enjoy the Lapidary Digest and have learned so much
from all who contribute. And that is what prompts this note.

Lapidary has been my hobby since 1955, but I have never
enjoyed myself more than this past week. I took a 5 day
class on doing Intarsia from Jim Kaufmann in Sedona, AZ.

What a beautiful area and what a satisfying experience.

Jim has received many awards for his Intarsia and is
willing to share and teach this art. I realized two things
which I encourage all of you to consider:

1. Time spent with someone who is tops in their field is
extremely satisfying and rewarding.

2. Intarsia, done properly, is a lot of fun and very

I highly recommend Kaufmann's studio (,
but I also encourage all of you to take advantage of the
many schools out there to further your experience and
proficiency. I had never done anything like this and just
wanted to pass along how satisfying it can be.

Jack Haslup

Subject: NEW: Cutting and Polishing Peridot Cabs


I decided to try my hand at turning some of the rough
peridot I have into cabs without the typical methods (since
they're small chunks instead of slabs anyway). I used a
diamond burr to form and smooth the cab, and it seemed to
turn out OK.

The problem is, I don't know how to polish the stone now.
Any advice? Is there any way to polish peridot with typical
metal polishes, such as rouge? I don't have any of the
proper lapidary polishes (oxides and the like), and would
like to utilize what I have now if it's possible.

Also, is there anything I should know about using the method
I did? For example, if the diamond burr would somehow have
damaged the stone without me knowing? As it is, I think I
did a decent job of making a cab for my first try, but I
don't want to continue doing this if I'm effectively ruining
perfectly good material.

Any help is greatly appreciated!


Subject: NEW: Sphere Making Motors?

OK, I'm hooked on making a Sphere Making Machine. A little
something to do with those large but not quite gemmy chunks.

The original Lap Journal plans called for "Dayton" shielded
gear-reducing fractional motors. My Internet search revealed
nothing on Dayton Motors anymore. Probable out of business
or absorbed?

Any alternate recommendations as to motor source?

Fred G.
Miami FL

Subject: NEW: Blue Opal & other Cutables

(This was submitted by Terry Vasseur in response to a BIO
from Gladys Reyna which appeared in the last issue (#213).
For some reason, Terry could not contact Gladys directly and
asked that I pass it on. I think this will turn into a big
thread, so I am giving it a NEW subject. In the BIO, Gladys
said: "We normally work with BLUE OPAL, GEM SILICA
South American gemstones.)

I read your BIO on the Lap Digest. Welcome aboard.
I have some pieces of blue opal I acquired last January at
Quartzsite, possibly from someone you know.

My first question is: how many sources are there
for that material? To date, I've only experimented with a
couple of the smaller, lower quality pieces I bought, and
the results were pretty good. I've cut a lot of opalized
wood from Nevada and have found the Peruvian blue cuts
and polishes very much like that.

My next question has to do quality of the material.
The material I have is nice but it has a lot of inclusions.
The blue with white, similar to a cloud streaked sky, is
OK but the black and brown stuff detracts from the beauty.
What kind of material do you have available and are there
various quality grades?

Finally, I don't believe I have ever seen the other
materials you mentioned. I'm always interested in aquiring
and trying something new. Please tell us about them and
about any problems working them, and their prices.

I'm looking forward to hearing from you.

(In his original query, Terry asked that Gladys send him
a brochure and sent his home address, which I sent directly
to Gladys. The above is an edited rewrite of Terry's query.)

Subject: RE: High Speed Engravers for Lapidary Work

On Thu, 17 Jun 1999, you wrote:

<<Has anyone had any experience with using high-speed
engravers? These are essentially dental drills which turn
at a very high speed (~400,000 rpm) and are powered by air.

There is an article in "Compressed Air" magazine, June
1999 about these drills and their use in egg carving. They
feature the Paragrave tool, which they call "The Cadillac
of Cutters." Check out for
the article.


Subject: RE: High Speed Engravers for Lapidary Work

I used a Foredom "R" (hi-torque) and their high speed
handpiece for carving for years. Awesome. And a lot more
economical than buying a dental drill. I don't think a
dental drill would have the torque needed to carve hard

Mark Liccini

Subject: RE: High Speed Engravers for Lapidary Work

Hi Hale,

I've not used them, but Charles Kelly in Tucson does some
fantastic reverse intaglio in large pieces of transparent
gem material (quartz family mostly). One of his pieces has
several lady bugs resting on a plant stem. They're so small
you need a loupe to see them.

If I remember correctly, he was featured in Lapidary Journal
a year or so ago.

He uses an air driven dental handpiece & many dental tools
that the tool accommodates.


Subject: RE: Searching for Nephrite Headstone

Craig, your advice was very good about getting hold of Fred
Ward. I sent the lady in question his e-mail address and
the URL for the jade website which he is associated with.

Hope she finds what she needs. (She thanked me very
politely, too!)


Subject: RE: Corundum- Cutting and Shaping Ruby/Sapphire

One of the best kept secrets in the Lapidary field is that
North Carolina Corundum is a different breed of cat! It's
about 1/2 a Mohs' number harder than it has any right to be,
so it is difficult to work.

I'm not surprised that it ate a SiC wheel; I used to use a
NC Sapphire to dress my Highland Park (R) wheels before I
graduated to diamond!

I'm not so sure about what happened to the saw; it may have
been nearly worn out to start with and the Corundum finished
it off, or it could be that it was approached too boldly;
if you're going to cut Sapphire with a saw, try to figure
out a way to approach the saw S-L-O-W-L-Y.

You don't "CUT" NC Sapphire; you WEAR your way through it!
Otherwise it can shatter your diamond. (We forbid Corundum
on the Club's Genie, for that reason; I have seen tracks
ground in new diamond wheels by people who didn't know that
you approach Sapphire with great respect! My wife, on the
other hand, has been making Sapphire cabs for almost ten
years on the same wheels.) If you work everything slowly
and with a feather touch, NC Sapphire shouldn't be any more
difficult than Indian; but if you get rough with it and try
to work fast with a heavy hand, I guarantee disappointing

Ted Robles (

Subject: WTB: Cutting of Rocks with a Large Saw

Would like to get someone with a 14" or larger saw in the
Toledo, Ohio, area to cut fieldstone boulders. Please
contact me at any of the addresses given below.


Stephen V. Foster, GG
25001 w river rd, perrysburg, oh 43551
cellular 419-297-3900; ph 419-878-3900
fax 878-5488

Subject: BIO: Keith Cheadle

Hi Hale.

I started lapidary 1952 and along the way I added mineral
collecting, micro mounting, fossil collecting, gold dredging
and detecting, also faceting.

They all gets their turn eventually in between fossicking
trips and whatever else has to be done.

I most appreciate the chance to join your great listing.


Keith Cheadle

Subject: BIO: Robert Redden

Hello, My Name is Robert Redden

I have been a lapidary for 2 1/2 years. I enjoy cabbing
and tumbling. I like to learn from and teach others about
the lapidary arts. I am taking a geology course and hope
to be more knowledgeable in a few months about the field.

I would like to hear from anyone interested in the same.

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