iandol on tue 11 feb 03
Dear Janet Kaiser,=20
The answer is to first put the cobs of granite through a bisque firing. =
This seems to induce sufficient thermal stress to make the crystals of =
this that and the little bits of gold break apart with ease. Pan the =
gold then ball mill or Dolly Pot the rest after picking out all of the =
black bits. Then pan the gold a second time to remove the Fool's Gold.
Shap has a great Granite and is a bit closer than Aberdeen.
Best regards,
Ivor Lewis.
ps. Had a great day when Avril Farley called in. Let her overcome =
withdrawal symptoms with some nicely aged Porcelain clay.
Janet Kaiser on tue 11 feb 03
Sorry, but I am having difficulty with this particular do-it-yourself
exercise! But then again, I suspect that what one person regards as
granite, is not what others would equate with the word... Our local granite
(for example) is used to make "the best curling stones in the world". The
"best" being the hardest and longest lived (like Hendley Mugs, they have a
life of their own and are often left as precious items in people's last
will and testament :-)
This curling stone granite is actually only quarried at a place called
Trevor, then exported to Scotland and Canada for the other production
processes and steps. They have more or less demolished one mountain in the
past 200 years and have two more to go... Shame because Tre'r Ceiri (Town
of the Giants) is the pretty impressive Iron Age fort on the top of one. A
"conflict of interest" is programmed for approximately 5-10 years from now.
But I absolutely boggle at milling this particular granite! It is so
extremely hard... Just to give an example: my parents needed 12 bits to
drill a single hole into the wall of the granite cottage I grew up in...
The cost of bits almost equaled the cost of the wood and glass
lean-too/conservatory/kitchen they were adding to our one-up, one-down
abode at the time. Of course that was "old" granite which was well and
truly "off", the cottage being well over 100 years old, but even "fresh"
granite is still awfully hard... At least it is here! Not to mention that
granite, means "unyielding" figuratively speaking too...
OK, yes, drills as well as bits have improved tremendously in the last
40-odd years, but I would not personally dream of expending all the energy
necessary to mill "our granite" myself. The most obvious source of "granite
dust" would have to be the local craftsmen who make granite counter tops,
grave stones, etc. It may have some marble "contamination", but the
alternative (weeks of milling) just would not be viable, either
economically or environmentally.
I suppose the bottom line would have to be "know your granite". As a
"granular crystalline rock of quartz, orthoclase felspar and mica or
hornblende" there must be grades of hardness? Like slate and any other type
of stone? We have pretty hard slate here in North Wales too, with a minimum
life expectancy of 200-300 years for roofs. When compared to the 50-100 for
Spanish or Chinese (much cheaper) slate, it is a measure of the differences
one can expect in "quality".
Incidentally... These pre Cambrian granite mountains are geologically
speaking tiny residual stumps of a much larger mountain massif, which have
eroded away over the millennia. The clay deposits found in "The Potteries"
are the result of that erosion, including a couple of Ice Ages. It is all
quite fascinating!
BTW I have just acquired a "Ceramill" made by WMF... "with the exclusive
ceramic grinding mechanism. For salt, pepper, spices and dried herbs.
Harder than steel. 10 year guarantee on the millstone". It cost a whopping
=8018.90 (where =80 =3D Euro) so it better live up to the blurb! All
because we cannot buy ground caraway here... Never mind granite... :-)
That was the only ceramic news I can share after my week in Germany... Oh,
except if you ever visit Meissen, expect to pay a minimum of 400 Euros for
the tiniest vase...
Again... It was most interesting to compare the prices of manufactured
(albeit "hand-painted in Germany") wares on sale in the big department
stores (incl. the average 800% mark-up) to what "real potters" can ever
expect to get for their work. A depressing reminder of how out of touch
with the real world we ALL are!! No wonder galleries make accountants shake
their heads in disbelief... 800%... Now that would make economic sense... A
real business instead of a social service... Hummm... I wonder what the
fifty-odd potters we work with would say to that suggestion?!?!?
Sincerely
Janet Kaiser - home to find "no-mail" did not work, so over 900 e-mails to
plough through! The week away from the coast has done me and my joints a
lot of good, although just three hours of being back in this damp has me
stiffening up nicely. My PC has also developed an annoying whistle whilst I
have been away... Back to work tomorrow. Ay, ay, ay...
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The Chapel of Art / Capel Celfyddyd
8 Marine Crescent, Criccieth LL52 0EA, Wales, UK
Tel: ++44 (01766) 523570 URL: http://www.the-coa.org.uk
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