Pretoria Gem and Mineral Club

Pretoria Gem and Mineral Club
Affiliated to the Federation of Southern African Gem
and Mineralogical Societies
October 2007
Pretoria Rockhound Digest
The Pretoria Gem and Mineral Club
Clubhouse: No. 29, 26 th Street
P.O. Box 36888, Menlo Park, 0102 Menlo Park, Pretoria, Tel. 012-460 1494
Pretoria Every Saturday from 10:00 to 17:00
South Africa
website: www.fosagams.co.za/pgmc
e-mail: pgmc@fosagams.co.za
Chairman: Douw Steyn 083 260 7416 a/h Vice-Chairman Dieter Heinichen 012-991 5839
douw@flintsteyns.co.za Secretary: Di de Villiers 082 562 8983
pgmc2@fosagams.co.za
Treasurer: Dave de Villiers 083 337 1541 Editor: Heidi Naudé 072 923 2180
pgmctreasurer@fosagams.co.za
heidinaude@absamail.co.za
________________________________________________________________________
Programme Highlights for October 2007
*** Mineral Meeting 2 October
*** Annual General Meeting
Swop and Sell and Social
6 October
*** Geological Outing: Faerie Glen Nature Reserve 28 October
Regular Meetings at the Clubhouse:
Monthly Club Meeting, Swop/Sell & Social
and Monthly Programme – Talk/Slide Show
- every First Saturday of the Month
Monthly Mineral Meeting
- every First Tuesday of the Month
Monthly Faceting Meeting
- every Second Saturday of the Month
Workshop Maintenance (19:00 – 21:00)
- every Second Wednesday of the Month
Silversmithing Meeting - every Thursday from 19:00 – 21:00
The Clubhouse is open every Saturday from 10:00 to 17:00. No Smoking in the Clubhouse please!
Editors Corner
Time for some serious spring–cleaning! Have you already sorted and cleaned the rocks and minerals collected
on the recent outings? Thought so! No club outing is planned for October as yet, this would therefore be
a good time to empty all those crates, paint tins, boxes and plastic bags stored in the garage.
Sort the stuff first into categories: display, work (lapidary, tumbling), swop & sell, garden or scratch patch at the
clubhouse! I know it’s hard to part with those self-collected specimens, but what good is it to keep them all hidden
away unappreciated somewhere in the garage corner? Like it or not, you need to make space for the material of
the next outings and the Gemboree!
The club highlight for this month must surely be the Annual General Meeting; please come and join us, you are
all most welcome. Important issues need to be decided and agreed upon for the new financial year, don’t let this
opportunity pass you by, let your voice be heard and make your vote count – hope to see you all there.
Heidi Naudé

Detailed Programme for October 2007: (as at 25.09.2007)
Date Event Time Contact Details
2 Oct. Mineral Meeting: Brandberg Minerals 19:30 – 20:30 Horst Windisch, 012 – 460 7572
4 Oct. Silversmithing – workshop open 19:00 – 21:00 Lex Krabbendam, 083 449 6812
6 Oct. Annual General Meeting
Swop & Sell and Social
13:00 – 14:00
14:00 – late
Douw Steyn, 083 260 7416
11 Oct. Silversmithing – workshop open 19:00 – 21:00 Lex Krabbendam, 083 449 6812
13 Oct. Lapidary & Silversmithing workshops open 10:00 – 17:00
16 Oct. EXCO Meeting 19:00 – 21:00 Douw Steyn, 083 260 7416
18 Oct. Silversmithing – workshop open 19:00 – 21:00 Lex Krabbendam, 083 449 6812
20 Oct. Lapidary & Silversmithing workshops open 10:00 – 17:00
25 Oct. Silversmithing - workshop open 19:00 – 21:00 Lex Krabbendam, 083 449 6812
27 Oct. Lapidary & Silversmithing workshops open 10:00 – 17:00
28 Oct. Geological Outing: Faerie Glen Nature Reserve 09:30 - …… Markus v/d Neut, 083 455 7168
Cabochon classes by appointment - contact Linda Stone any Saturday Linda Stone, 012-803 1398
(after 16h00)
Faceting classes by appointment - contact Phillip Alp any Saturday Phillip Alp, 014-574 3488 (h)
or 014-571 2159 (w)
Duty- and Opening/Closing Roster:
October 6 13 20 27
Open Charles Piet Klaus Charles
am A(7) Charles / Heidi I(6) Piet / Elise K(6) Klaus / Karin A(8) Charles /Melinda
pm Closed J(5) Dave / Di B(6) Johan / Hannie D(6) Nico / Fay
Close Douw Dave Lex Fay
November 3 10 17 24
Open Wolf Dieter Charles Piet
am C(7) Wolf / Melinda E(7) Linda / Dieter A(9) Charles / Heidi I(7) Piet / Elize
pm Closed F(7) Anton / Magda H(7) Helmut / Anny J(6) Dave / Di
Close Douw Anton TBA Dave
Should there be any queries regarding workshop duties, opening or closing please contact Linda Stone at 012 – 803 1398 after 16:00.

1. Duty Roster / Thank You
Please check your duty dates on the updated roster (see page 2) and if not available, organize somebody
to “stand-in” for you in good time. Any confirmed changes or problems should be reported to Linda Stone,
who has kindly agreed to tackle this task; on behalf of the Committee a big THANK YOU to Linda.
The Committee would also like to thank all those duty members who have done additional duties,
sometimes on very short notice; the absolute champion of the duty circle must surely be Charles Strydom.
Ever so patiently, he is available for opening/closing the clubhouse and providing technical assistance and
advice to members wishing to cut or grind their stones. THANK YOU Charles, we really appreciate you.
2. Machine Maintenance
Ongoing problem, we still need members willing to assist to come forward. The
maintenance sessions will be changed back to the second Wednesday evening of
the month. Please contact Lex Krabbendam if you are willing and able to assist
with this task. Kevin Hean has agreed to do a technical overhaul on all our saws.
Quotations will be obtained for each saw after the financial year-end and once the
costs have been accepted one saw after the other will be sent to his workshop.
3. Membership Data Base
The manual database is up-to-date; however, the website database is still a ”work in progress”. It is vital
that you contact us immediately should your postal address, telephone number or email address change to
keep our records updated, thus ensuring that you receive all communications due to you.
We would like to appeal to the snail-mail members once again to inform us immediately when we can
change them from snail-mail to email; not only does that save quite a substantial amount of admin costs
(printing expenses, envelopes, postage), for the club, it also ensures that you do receive the club
communications much faster and more reliable than with the postage system.
Any changes required can be sent either via SMS to 072 923 2180, or via fax to 012 250-2709 or via email
to heidinaude@absamail.co.za for rectification. Thank you very much for your co-operation.
4. Annual General Meeting – 06.10.2007
.
Please mark this important date in your calendars and join us at the clubhouse on
Saturday, 6 th October at 13h00. Important issues such as committee member
elections, membership fees, workshop fees, club programme issues etc. for the
new financial year are on the agenda.
This is a meeting not to be missed; all members are welcome; see you there!
5. 2008 Gemboree
The first Gemboree communication has been distributed and the second one with the booking information is
well on its way. Please note that the registration date for the Gemboree has changed from previously
1 st October to now 15 th October 2007 to allow everybody (email and snail mail members) an equal chance
for the reservation of accommodation. Remember that accommodation in the part of the world is limited and
registration will be strictly on a first come first serve basis.
If you snooze you will loose (or end up camping).
Any enquiries should be directed to our chairman Douw Steyn at 083 260 7416 or our faithful secretary,
Di de Villiers at 082 562 8983, both numbers preferably after hours.

6. 50 th Anniversary Publication
Our Honorary President, Horst Windisch, has compiled the information of the PGMC club history – the
whole 50 years of it ! The Committee has proposed to issue a comprehensive information booklet, similar to
the 40 years anniversary, but this time with some photos from the archives of our “old” members.
May we therefore request you, our much-respected older members, to search your home archives, photo
albums, and even shoe boxes for some really old photos of the club or club outings?
The club has moved quite a few times during the early days, has anybody got photos from the first, second
or third club premises? What about a photo of the first machines acquired, with members of course. What
about a photo of the first club committee, etc. etc..
I think you all get the point. So please help us with this mammoth task; each photo received will be returned
to its rightful owner. I will also schedule interviews with our current honorary members still residing in the
Pretoria area, so please be warned, I am looking for some really interesting stories!
7. Personals
It was nice to see our honorary member, Klaus Binding, visit us again at the club on Saturday, 22.09.2007.
Klaus underwent some surgery to his leg recently and is recovering rather slowly, with his leg still being very
painful. Luckily he is still in good spirit and we enjoyed his company and that of his new friend, a previous
emerald miner of Zimbabwe, very much.
1. Monthly Mineral Meeting, 2 nd October 2007
The next mineral section meeting will take place on
Tuesday, 2 nd October 2007 at 19:30 at the clubhouse.
The subject for discussion will be “Brandberg Minerals”,
thus bring along your favourite quartz, amethyst and
prehnite crystals from this locality.
This should prove to be one of the outstanding displays
of the year.
For those who are not yet familiar with the Brandberg
region in Namibia, this is the meeting to join. Here you
will be able to gather all the required information and
hopefully see many fine crystals originating from this
famous area.
This could also be very informative for those who plan
to attend the next Gemboree in Uis, Namibia, as the
Brandberg area will be one of the places we will visit.
So come and join us for an unforgettable and very
educational evening.
This will also be the last Mineral Meeting for 2007.
Horst Windisch

2. Rustenburg Show
Please note that the Gem and Mineral Show planned
for Rustenburg at the beginning of October has been
cancelled until further notice.
First information received was that only seven dealers
and one mine had signed-up for the show, which is
unfortunately too little to warrant such an event.
But all is not lost and if everything goes according to
plan the show might take place at the beginning of 2008.
Members will be kept updated via future newsletters.
3. Monthly Club Meeting & Monthly Programme
No Monthly Club Meeting has been scheduled for
October 2007. This is due to the Annual General Meeting
taking place on 06.10.2007 at 13:00.
No Monthly Programme Meeting is planned for October;
as the new basic arrangements, such as dates and
frequency of this event must be decided upon at the AGM.
The Swop and Sell and Social will continue as planned.
4. Cabochon Competitions
The next PGMC Club Competition will close on the
27 th October 2007. Entries must be submitted to the
duty members by latest 16:00 on that day.
The material requested is Jasper (any variety) and it
will be for “standard form” cabochons only.
Good luck to all entries!
Linda Stone
5. Southern African Gem Cutting Challenge
Gem cutters - closing date for this year is 10 November -
we have secured prizes for 1 st , 2 nd and 3 rd placings - so
things are slowly moving forward - please try and submit
an entry to us.
Any stone may be entered for the cabochon section,
provided it is symmetrical i.e. round or oval, and any stone
again may be entered for the faceting section - the design
to cut this year is the rectangle emerald cut.
For more detailed info visit www.sagams.co.za and click
onto our page on the left.
Let's try and lift the standards in this region - enter your
favourite type stone and show us what you can do.
It takes courage to enter a competition, and as my late
master Rex Alp once said - competitions separate the men
from the boys !
Please feel free to contact me for further information.
Good Luck.
Fay Pierides (pierides@mweb.co.za, Tel: 012 991-1474)

6. Lapidary Material - C&M Landscaping
Just a short reminder that C&M Landscaping, corner Lynnwood and Meadow Streets, Willow Glen,
Pretoria offer tumbled and rough lapidary material by the ton at competitive prices. Linda Stone
discovered this source and intrigued, I checked it out myself.
Red Jasper, Brecciate Jasper, Picture Stone, Yellow and Blue Tigers Eye, Rose Quartz, White or Milky
Quartz, Unakite and Bone Stone are offered for sale as big massive boulders ranging from 5 kg – 50 kg
each. The average price is R 5.00 – R 6.00 per kg. You can also buy the above and many more varieties
as smaller rough or half tumbled pieces, sold in 20 kg packages. These pieces would only be for tumbling
purposes or to display in your garden. The prices of those range from R 119 for tumbled (not polished)
Unakite to R 60 per bag for various rough Quartz varieties, Tigers Eye and Jasper varieties.
This does obviously not compare to our club outing experiences, however for those who are not fortunate
enough to go out and collect rocks and minerals themselves, it may provide an affordable alternative.
It is quite an experience to walk through rows and blocks of material and to listen to some strange names
of the rocks and their locations provided by the eager sales personnel.
Heidi Naudé
7. Geological Outing to the Faerie Glen Nature Reserve – 28 th October 2007
Participants to meet at the parking place of the Faerie Glen Nature Reserve, Genl. Louis Botha Avenue,
Faerie Glen, Pretoria for a 09h30 am departure.
We will hike along a well-marked footpath up to the top of the Faerie Glen Hill, from where we will enjoy a
good overview of the eastern suburbs of Pretoria. Various geological features will be pointed out to you
along the way, including a good example of fault Breccia at the top of the Daspoort Formation, which forms
the hill.
On our way down, we will see a weathered Diabase sill (an igneous rock), as well as the contact between
the shale of the Strubenkop Formation and the Andesite (a volcanic rock) of the Hekpoort Formation.
This is one of the few locations in Pretoria where one can see this contact clearly, as contacts are often
concealed by urban development or vegetation.
Afterwards we can enjoy some refreshments at the Plumbago tea garden. Please bring some good and
comfortable hiking shoes, a water bottle, hat and sun cream and sun glasses along (depending on the
weather conditions. Entrance to the nature reserve is free.
Please contact Markus van der Neut at 012 – 998 6443 or 083 455 7168 after hours if you want to
participate at this outing.
You might be a rockhound if:
- You own more pieces of quartz than underwear.
- Your rock collection weighs more than you do.
- Your rock garden is located inside your house.
- You have to respond “yes” when asked, “what have got in there,
rocks?”
- You purchase things in bulk such as 20 ltr. paint, just to have a
nice bucket to haul your rocks in.
(Courtesy of Horst Windisch – Excerpted from Lithosphere 4/96, via “The Pegmatite”, March 2005)

1. Note of Concern – Behavior on Club Outings
The following note of concern was received, I quote:
“Most true rockhounds today realize how difficult it is to procure suitable collection sites for
material, irrespective of which field they are interested in. I have had the pleasure, during
the last few months, to attend two very successful cutting/tumbling material field trips.
On both occasions there was ample material to collect from the countryside as well as some
to purchase from the hosts.
I must however express my concern over a particular aspect of these outings:
On both occasions out hosts offered stockpiled material FREE OF CHARGE, most likely
assuming that the collection would be moderate.
Embarrassment is an understatement, as some individuals resorted to pure rock-gluttony on
the FREE OF CHARGE stockpiled material, without having collected anything substantial on
the field trips or by way of purchase.
I am pretty sure our hosts noticed this behavior, which may in future make them think twice
before agreeing to host an outing. Moderation is a virtue.”
John Bruigom
End of quote.
We would like to appeal to all concerned – please do not spoil future outing possibilities for other
members; there is more than enough for all of us and future generations to share and enjoy together.
2. Monthly Programme – Micromount Photography by Wolf Windisch
On 1 st September 2007, eighteen club members were privileged to attend a Micromount Photography
Presentation given by Wolf Windisch. This was truly an exceptional insight into this man’s collection
and ability to show us the most exquisite specimens of his own collection and photographs made by
him personally.
In my opinion, Wolf can compete with any photos shown in mineral books or mineral calendars I
have seen from overseas. He explained the technical aspects of three-dimensional photography, depth
of field and how to put certain parts of photos in sharp focus.
Then he took us through the practical way of how he puts his photos together by taking pictures of parts
of the object using his specially designed – holder, lens and lifter apparatus, which lifts the object at
1/10 of a mm intervals. These images are later sort of pasted together with the help of a special software
program named Helicon Focus, designed by a Russian fellow from the Ukraine, and voila – here is a
wonderful photo of another Micromount specimen. He also takes photos through his Microscope.
His high-tech equipment includes a top of the range Microscope and Camera, various lenses, as well as
a dirty toothbrush and an old ice-cream scoop – truly a very innovative person.
He showed us many magnificent specimens ranging from 1 – 3 mm in size, all collected by himself during
his numerous field trips during the past 10 years. His current collection consists of roughly 12 000 specimens
and believe it or not, they are all nicely stored in little plastic boxes, all labeled with names or as
unknown, date and place collected from and packed neatly in slim drawers for easy access.
All his photos were beautiful – however, his Pectolite Bird was the winner for me.
On behalf of the lucky members who attended his presentation - thank you Wolf, for sharing your wonderful
talent and collection with us.

From the Press – Dieter Heinichen
In the Pretoria News of 24 th August 2007 there appeared a short summary under the heading
“Gem find changes the history of the Earth”.
This SAPA-AFP sourced report is based on a publication in the journal Nature and states the following:
“Scientists have discovered what they believe are the world’s oldest diamonds beneath the Australian
outback in a surprise find that could force a rethink about how the earth formed.”
“The diamonds were found trapped inside zircon crystals from the Jack Hills region in the remote north of
Western Australia state. The 50 gems are tiny with the largest measuring only 70 micron, or about the width
of a human hair and most invisible to the naked eye.” According to the Australian (Alexander Nemchin,
Western Australia’s Curtin University of Technology) and German researchers “the diamonds are believed
to date back more than four billion years, making them almost as old as the 4,5 billion-year-old planet.”
This makes these diamonds about one billion years older than those previously considered the oldest.
Nemchin concludes: “It means it’s possible that the earth looked similar to the modern earth much earlier
than we thought. It is a very controversial area though and not everyone will agree with that conclusion.”