Issue No. 88 - Tuesday March 18, 2003
Moderated by: Thurmond Moore III
Committed to carrying on the fine works of
Hale Sweeny and Jerry Dewbre


From the Moderator: 

Topical Focus for This Week:


HOMEWORK for  tonight:

For each night this week, put on your thinking caps and share your experiences,
pains and pleasures in cutting Deeply colored Garnet and other Deeply
saturated stones.

Consider the following while you compile your responses.

1. Cutting garnet and other stones in the various color saturations

2. Intent:  cutting "bright and lively" stones, from rough that reaches
50% saturation (white paper test limit), or darker.

3. How approaching or exceeding the critical angle, or other parameters, might
help accomplish this.

4. Known cuts that perform well in darker garnet rough.

Phil in Florida submitted this topic for the first of a new series of week
long topical "clinics"  or group "brainstorming sessions".


Hi all,  Our focus topic has quite a bit of information today. We still have 3
day's left for this week's topic so get your post in today.

Index to Today's Digest

01  RE: Garnet and Dark Stone Clinic
02  RE: Garnet and Dark Stone Clinic
03  RE: Garnet and Dark Stone Clinic
04  RE: Garnet and Dark Stone Clinic
05  RE: Garnet and Dark Stone Clinic
06  RE: Garnet and Dark Stone Clinic
07  RE: Garnet and Dark Stone Clinic
08  FS:  Graves Mark IV
09  NEW: Flat Lapping


Subject: About dark stone
Date: Mon, 17 Mar 2003 16:04:21 -0500
To: lapidary%caprock-spur.com%SSSS%SSSSX06@ssss.gouv.qc.ca
From: mbegin@is.jgh.mcgill.ca

I will be a must  for me .
I tried to cut a red Zircon , I choose the right design for the
approppriate R.I. but the result
was very dull.....
since that time I was waiting for add. info...


Subject: Re: Dark garnet problem
Date: Mon, 17 Mar 2003 17:30:53 -0600
To: LapidaryArtsDigest <lapidary@caprock-spur.com>
From: Downey <alckytxn@swbell.net>

Howdy Folks,

I've found that the old recommendations for darkening light rough work
MUCH better than the ones for lightening dark material.
It does seem to make sense to use one of the tricks used with
tourmaline that has the dark C axis. That is to just use steep angles on
the end of baguette/long emerald type cuts and go for reflections across
the short dimension. Add interest with the crown too by increasing the
number/complexity of facets. Bar and opposed bar designs may help here.,
thus longer path lengths in some cuts.(some triangle/trillions are like
this). Avoid deep cuts with barion/break facets in the high 40s to low
50s angles as these will often create 3 bounces(very dependent on the
actual design. Remember, many garnets have a very high RI. Try to get a
good ID on your rough and cut at the CA or slightly above. Curiously,
there could be some good arguments for trying apex cuts with garnets.
You get a more complex crown, adding reflective interest, and you can
use pavilion main angles 2-3 degrees BELOW CA.
I'd like to see GemCad or other application which would allow for
entering a variable which would gradually extinguish the 'traced rays'
with increased path length. That would give you a good tool for testing
garnet/dark material-specific designs.
Another way to decrease depth of the stone would be to use a carving
technique to 'drill' an 'inverted' pavilion.  A polished,concave cone
leaving an 'anular' culet, whose sides of course would create an
included angle of around the stone's CA. hard to describe in words.
Sorry. Probably not practical for inexpensive material.
I've never heard of much heat or other treatment to light garnet. I
realize they have a poor reputation for heat sensitivity, but perhaps a
technique could be developed?
Choose Rough Carefully.
Earth's Dark Unconquered by Man.
Garnets Yield No Light.

1 Lucky Texan


Subject: Cutting Dark Garnets
Date: Tue, 18 Mar 2003 10:36:58 -0500
To: faceters@caprock-spur.com
From: "Douglas Turet" <anotherbrightidea@hotmail.com>

Hi all,

     This may be one of my shorter postings, as I'm up to my eyeballs in
work orders (a situation I don't mind "suffering", every now and then!).
First, I should admit it: even though I do this for a living, I do have my
favorites, and Garnets are easily among them!!! After all, what other
gemstone genus offers so much bang for the buck, so wide a tonal spectrum,
for so little money, and is so easy to polish? When confronted with the
larger, darker pieces of materials like Almandine and Pyrope, I choose one
of four options. I either...

1)  cut my pavilion mains at 41 degrees, then place "Zircon Cut"-style culet
facets at the midpoints between these facets, at 38 degrees, then use crown
main facets on not more than 35 degrees and allow for a table facet of not
less than 60%. (OR... )

2)  double the number of my pavilion mains, which I cut at 37 or 38 degrees,
then use an apex (pointed) crown design, whose 8-10 degree apex facets fall
at the midpoints between the pavilion main settings. This vastly improves
the brilliance and scintillation of the piece, even in cloudy daylight,
since each ray entering the stone is split and reflected in two. (OR... )

3) produce a "mirror cut" with 39-41 degree P-mains and 34 degree C-mains. A
mirror cut, as its name suggests, is any design whose pavilion facet
arrangement is repeated again, above the girdle. So, the Single cut and the
Portuguese would both be considered mirror cuts, whereas the SRB would not.
I usually only execute this option with the darkest pieces, or those too
heavily veiled for more traditional approaches. (OR... last, but not
least... )

4) Produce a non-round "Skylight Variation". In my lexicon, a "Skylight" cut
is any apexed cut other than a round, which uses only the most basic number
of facets possible. A great example is a square, whose crown consists of
four facets at 11 degrees. If you'd like to see how effective this can
really be, try it over a complex pavilion like that of Jeff Graham's "Gram
Princess", in a 12 or 13mm Almandine, using a pavilion (i.e. "culet") main
angle of 41 degrees. What's so cool about these cuts is that they tend to
get the viewer both intellectually and emotionally involved, as they peer
down into a stone's pavilion (often for the first time), and find themselves
"wandering around" in there! (And if you can get 'em emotionally involved,
you can't get 'em NOT to buy! Very cool stuff, especially in an economy like
this one!
     ...Hey, wait a minute! Didn't I say this was going to be one of the
shorter messages? Oh well, "the best laid plans", and all of that.

All the best,

Douglas Turet, GJ
Lapidary Artist, Designer & Goldsmith.
Turet Design
P. O. Box 162
Arlington, MA 02476, U.S.A.
Tel. (617) 325-5328
Fax: (928) 222-0815
Email: anotherbrightidea@hotmail.com


Subject: Re:Dark Stone Clinic
Date: Tue, 18 Mar 2003 14:24:42 -0800
To: faceters@caprock-spur.com
From: Phillip L Stonebrook <plstonebrook@juno.com>

Greetings list and Tony..

<<I have seen only very small stones that have any good brilliance to
them when conventionally faceted.>>

Yes, I agree. I have a great 5mm SRB out of pyrope garnet, the standard
Arizona "ant hill" variety, which is over the 50% saturation point, and
it performs nicely using angles just above CA and shallow crown angles.
That's one time I got lucky.

<<Mike in Florida has pictures that illustrate the problem nicely the two
dark garnets show about 50
percent occlusion. It looks Mike has succeeded in getting the most life
out of them though.>>

I also visited Mike's link to view his stones, and I have to agree, he
did a great job on these. I'm not familiar with Jim Perkin's Derek cut,
but it shows a 12 fold symmetry, with approx 65% depth to width ratio.
I'm not sure the cut is producing this performance, as most SRB's with
standard 16 fold symmetry with pavilion angles just above the CA and
shallow crowns will perform nicely in the 7mm size Mike showed. However,
this IS one example that fits the "dark stone clinic" criteria.

Jim .. care to share the Derek" cut with us, and your findings in dark
rough to produce "bright and lively" gems?

Best regards...
Phil in Florida


Subject: Re:Dark Garnets
Date: Tue, 18 Mar 2003 13:54:42 -0800
To: faceters@caprock-spur.com
From: Phillip L Stonebrook <plstonebrook@juno.com>

Greetings list and Dave

<<Thurmond - The light needs to be returned in a minimum number of
bounces since each bounce causes energy loss in dark material. Please
correct me if I am in error with this line of thinking.>>

<< Dave - As long as you are above the critical angle on the internal
reflections, the number of bounces is not important (total internal
reflection = 100%). The absorption of light is proportional to the total
path length traveled through the stone.  In a thinner stone, you have a
shorter path length, so there is less absorption and you have a brighter

Perhaps you have not thought about this before, but the number of bounces
_directly_ determines the total path length of the light ray in a cut
gem. A trilliant designed with angles for a triple bounce before ray
emerges will have a longer path length than a SRB gem designed for a
double bounce. I know we are not all gem cut designers, but this is one
consideration that we should all be familiar with, as our cutting
approach and choice of design requires it when trying to produce a
"bright and lively" gem in darkly saturated rough.

Thanks for contributing to our discussion.

Best regards...
Phil in Florida


Subject: Re:Dark garnet problem
Date: Tue, 18 Mar 2003 13:57:38 -0800
To: faceters@caprock-spur.com
From: Phillip L Stonebrook <plstonebrook@juno.com>

Greetings list and Dan..

<<I think you have agreat idea to address the problem of how to cut dark
garnets to get the brightest possible stone. I am not alone because one
of my online friends asked me check his design with BOG and GemFramX.>>

Thanks .. and thank you for contributing.

<<I don't trust GemFramx or BOG much with dark garnets until I can see
that they actually factor in saturation. I am a big believer in
raytracing gem designs but in this case I think it is of limited use>>

Neither GemCad nor BOG includes an actual color saturation capability. I
have "encouraged" Tom Herbst to somehow include color saturation within
BOG, possibly using a colorimeter like the Home Depot paint mixing setup,
however, due to his timing and the unknown parameters and standards
involved, this is still on the "wish list". As I said months ago,
""Someone will do this, and it will provide a great benefit to all "color
stone" faceting"".

<<I think a friend is working on some code that will take saturation into
account in raytracing ..<snip>.. I think POV may work better than either
of the other packages for dark garnet but I do not know.>>

I wasn't aware that others were working on this "saturation" problem, or
writing code to produce a program to address this. Is POV the name of
that program?

<<I am sure there are other factors but I think you can keep close to
critical angle and use low crown to get pretty good performance on dark
garnet. I think you just want a design close to critical angle with a
fairly low crown that gives a good pattern of light. I think you can
still use BOG and GemFramX but ignore the numbers look at the light
pattern then cut a test stone to confirm your designs. You don't want
dark areas with no light return but I don't trust any numbers until I can
confirm it myself. Your test stone is the ultimate test.>>

Yes, that is the conventional wisdom to date. My cutting experience with
darker rough shows hit and miss performance, but I am (and others are)
continuing to work on it. Once in a while I get lucky using these
conventional approaches.

<<If someone knows the solution please share it on the list.>>

My sentiments exactly! We're looking for more contributions on cuts that
work for dark rough, or your process to produce "bright and lively" gems
in dark rough .. and we'll all benefit from the results!

Best regards...
Phil in Florida


Subject: Re:Garnet and Dark Stone Clinic
Date: Tue, 18 Mar 2003 13:56:26 -0800
To: faceters@caprock-spur.com
From: Phillip L Stonebrook <plstonebrook@juno.com>

Greetings list and John...

I have read your post, and have gone to your website. Looks very good ..
good photography .. fast loading .. nice performance on the top gem,
second row from right but, no labels so .. what kind of garnet is it ..
rhodolite, as indicated by the RI of 1.76 in the JWW016.html?

I've examined your cut with GemCad and BOG. GemCad shows some light
leakage low on the crown B tier, and some high on the crown A tier. BOG
reports slightly lower numbers than you did; ISO=55%, COS=46%, which may
be caused by my not reproducing your diagram exactly. The numbers on the
pavilion depth and table width are as close as I can easily reproduce
from your html diagram. For those that wish to examine this cut in
GemCad, load the .asc file below.

GemCad 5.0
g 96 0.0
y 8 n
I 1.76
H JWW016.GEM 10/23/02 John Wright
H For dark garnet
a -90.000000 1.00000000 96 n G 90 84 78 72 66 60 54 48 42 36 30 24 18 12 6
G Cut to round
a -61.000000 0.81385338 90 84 78 72 66 60 54 48 42 36 30 24 18 12 96 n P1 6
G Level girdle
a -56.000000 0.77848737 90 84 78 72 66 60 54 48 42 36 30 24 18 12 6 96
n P2 G Step cut to match diagram
a -51.000000 0.75673218 96 n P3 90 84 78 72 66 60 54 48 42 36 30 24 18 12 6
G Step cut to match diagram
a -46.000000 0.75622014 96 n P4 84 72 60 48 36 24 12 G Step cut to match diagram
a -41.000000 0.79459561 90 n P5 78 66 54 42 30 18 6 G Polish in
a 44.500000 0.81883852 96 n A 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90
G Level girdle, establish girdle thickness
a 39.500000 0.79225638 96 n B 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90
G Step cut to match diagram
a 35.000000 0.77177770 3 n C 15 27 39 51 63 75 87 G Meet  B-A-B
a 25.000000 0.75139104 3 n D 15 27 39 51 63 75 87 G Meet C-B-B-C
a 0.000000 0.71388889 96 n T G Cut to 26.2% of overall width

Some observations: The pavilion goes from 16 fold symmetry to 8 fold on
the 4th tier, whereas the crown goes from 16 to 8 on the 3rd tier; this
causes a slight rotation in the crown which, if you look closely to your
ISO image, shows some slight "pin wheeling" in reflectance pattern.
Implications for darker rough are unknown.

I used BOG to "optimize" this design to see what the performance could be
"number wise", and BOG immediately tried to optimize below the CA of 34.7
degrees. This tells me this design has plenty of room for improvement for
maximum brilliance, or as you say, possibly P2 or P5 could be removed. If
you wanted to spend the time to take this design apart and put it back
together optimizing each tier as you go, it would improve in brilliance.

You state "I designed a cut that probably wouldn't make sense to most
yet, it has more brightness and flash than any other I've cut".
Conventional wisdom says for darker rough we should (theoretically) go
with shallow designs, geometry for a double bounce, a large table to let
in max light, broad pavilion facets to produce large reflectance
surfaces, and angles optimized to produce the "hottest" brilliance we can
get to blast through the darkly saturated rough. Your design actually
goes the opposite direction, and I would sincerely say this is a cut to
optimize lighter rough (kunzite) for decent brilliance and good color
presentation of the lighter saturation materials. Your modified crown of
less height should make an improvement for darker materials. Please don't
consider this as a "negative criticism" of your design; just that it
should work better for lighter materials where you want to accentuate
color saturation in lighter rough and where lower brilliance won't
"swamp" out delicate color shades.

Thanks for contributing to the "darker rough clinic" discussion. I
welcome additional submissions of cuts that work well in darker rough, or
your steps to produce such a cut. We're all looking for further answers
on this topic, and to what everyone else has found that works best for

Best regards...
Phil in Florida

Date: Tue, 18 Mar 2003 09:52:07 -0600
To: "LapidaryArtsDigest" <lapidary@caprock-spur.com>
From: "MR" <rugroden@attbi.com>

If anyone is looking for a faceting machine I have a Graves Mark 4
sitting around gathering dust.  It comes with a 45 degree dop, 64 & 96
index gears.  It's tight, doesn't appear to have been used much.  I
picked it up on a trip because of nostalgic reasons, I started on a
Graves, but now I'm running out of room in my shop for working tools and
my wife won't let me display it in the living room.  Go figure.  $300.00
plus stamp.



Subject: Flat Lapping
Date: Fri, 10 Jan 2003 20:27:11 -0600
To: <lapidary@caprock-spur.com>
From: "Wayne S. Barnett" <wayneb@ev1.net>

Does anyone out there have any ideas on houw to get a good polish on
limestone or marble on a flat lap.











PERSONALS: (General Lapidary and Faceting)




Lurking is fine, but participation is better for learning !
Post something from your experiences in gemcutting today!


Changed HR Policies

Casual Fridays:

Week 1 - Memo No. 1

Effective this week, the company is adopting Fridays as
Casual Day. Employees are free to dress in the casual
attire of their choice.

Week 3 - Memo No. 2

Spandex and leather micro-miniskirts are not appropriate
attire for Casual Day. Neither are string ties, rodeo belt
buckles or moccasins.

Week 6 - Memo No. 3

Casual Day refers to dress only, not attitude. When planning
Friday's wardrobe, remember image is a key to our success.

Week 8 - Memo No. 4

A seminar on how to dress for Casual Day will be held at 4 p.m.
Friday in the cafeteria. A fashion show will follow. Attendance
is mandatory.

Week 9 - Memo No. 5

As an outgrowth of Friday's seminar, a 14-member Casual Day
Task Force has been appointed to prepare guidelines for proper
casual-day dress.

Week 14 - Memo No. 6

The Casual Day Task Force has now completed a 30-page manual
entitled "Relaxing Dress Without Relaxing Company Standards." A
copy has been distributed to every employee. Please review the
chapter "You Are What You Wear" and consult the "home casual"
versus "business casual" checklist before leaving for work each
Friday. If you have doubts about the appropriateness of an item of
clothing, contact your CDTF representative before 7 a.m. on Friday.

Week 18 - Memo No. 7

Our Employee Assistant Plan (EAP) has now been expanded to provide
support for psychological counseling for employees who may be having
difficulty adjusting to Casual Day.

Week 20 - Memo No. 8

Due to budget cuts in the HR Department we are no longer able to
effectively support or manage Casual Day. Casual Day will be discontinued,
effective immediately.



From: "J Wagstaff" <wagstajo@kos.net>

Three little words...

I suppose some degree of commerce would grind to a halt if telephone
solicitors weren't able to call people at home during dinner hour, but
that doesn't make it any more pleasant.
Now Steve Rubenstein, a writer for the San Francisco Chronicle, has proposed
Three Little Words, based on his brief experience in a Telemarketing
operation, that would stop the nuisance for all time.
The three little words are: "Hold On, Please..."
Saying this, while putting down your phone and walking off (instead of
hanging-up immediately) would make each Telemarketing call so much more
time-consuming that sales boiler rooms would grind to a halt.
When you eventually hear the phone company's "beep-beep-beep" tone, you
know it's time to go back and hang up your handset, which has efficiently
completed its task.
Do you ever get those annoying phone calls with no one on the other end?
This is a telemarketing technique where a machine makes phone calls and
records the time of day when a person answers the phone. This technique is
used to determine the best time of day for a "real" sales person to call
back and get someone at home.
What you can do after answering: If you notice there is no one there,
immediately start hitting the # button on your phone, 6 or 7 times, as
quickly as possible. This confuses the machine that dialed the call and it
kicks your number out of their system. Since doing this, our phone calls
have decreased dramatically.
Other Good Ideas:
When you get "ads" enclosed with your phone or utility bill, return them
with your payment; let the sending companies throw their own junk mail away.
When you get those "pre-approved" letters in the mail for everything from
credit cards to second mortgages and similar type junk, do not throw away
the return envelopes. Most of these are postage-paid return envelopes, right?
Well, why not get rid of some of your other junk mail by putting it in these
cool little postage-paid return envelopes.
Send an ad for your local chimney cleaner to American Express.
Send a pizza coupon to Citibank. If you didn't get anything else that day
then just send them their blank applications back!
If you want to remain anonymous, make sure your name isn't on anything you
send them.
You can even send the envelopes back empty if you want to just to keep them
Eventually, the banks and credit card companies will begin getting their own
junk back in the mail. Let's let them know what it's like to get lots of
junk mail. Best of all they're paying for it...Twice!



From: "RICHARD P ROSENTHAL" <kenaii@earthlink.net>

I am looking for a primary source for  rough White Nephrite Jade, close
to point of origin, which is the Ho-Tien[ Hotan] or Yarkand area of
China. Contact Kenaii@earthlink.net I do have Carving and Gem grade
Green Nephrite Jade from Siberia for sale.


Get a FREE copy of the 2003 Faceter's Engagement Calendar
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If you're looking for quality facet rough please check out Rough to Cut,
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Contact b-daw@pacbell.net

Honey, red & brown zircons, 10g parcels @$20/parcel
Red Garnet $8/g, eye clean-slightly included
Spessartine Garnet $7.50/g, slight-moderately included
Malaya Garnet $6/g, good eye clean roughs
Tunduri Garnet $10/g, eye clean-slightly included
Pink Tourmaline $20/g, eye clean-slightly included
Red Tourmaline $10/g, slight-moderately included
Bicolor Tourmaline $15/g, eye clean
Watermelon Tourmaline $20/g eye clean
Green/Green Blue Tourmaline $10/g, eye clean roughs
Blue, Green & Blue/Green Sapphires $35/g, eye clean-slightly included, up to 1g.
Blue Beryl (Aquamarine) $6/g, eye clean-slightly included crystals
Green Beryl (Emerald) $10-$50/g, eye clean-slightly included crystals, zoned green
Cabbing Grade Aquamarine $3/g


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is produced by Thurmond Moore III

Tempie Francis, Attorney at Law / Legal Advisor

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