I almost signed up for a course on “metal clay” as a hobby then I
thought - what about just making tiny figurines of clay and other
mixes of stony matter and firing them in a kiln? Could anyone please
point to a source on where I might get started on this? BTW I made
one figurine of portland cement and clay and it was quite nice so I
put it in the microwave oven and it exploded. There has to be a
I almost signed up for a course on “metal clay” as a hobby then I
You are truly funny, micro wave eh? Perhaps the oven might have
helped, but what you realy need is a kiln, most jewelry tool
suppliers sell them, check them out and don’t kill your microwave.
I have read that a microwave oven can be used even to melt iron if
you put “refractory” material around the targeted object.
Or is “refractory” the correct word?
Anyway, microwave ovens are very cheap now so using them for “metal
clay” or other clay work might be a good idea.
Nothing wrong in making clay figures but beware of adding other
matter to the clay. People hve spent centuries making mixes of clays
and grog so you can go and buy something suitable for every job
regrdless of the size of the piece. The rate of rise for the
temperature in a microwave is totally unsuitable for firing ceramics.
you will not only get exploding pots but damage the oven itself and
possibly irradiate the user with microwaves.
I have read that a microwave oven can be used even to melt iron if you put "refractory" material around the targeted object.
I saw this little kit at a craft shop the other day that was a
refractory kiln for glass fusing in the microwave. Pretty darned cool
little concept, but I can’t imagine how effective it might be. Or
what it would make my food taste like the next time I wanted to use
Microwave ovens are designed to heat the water and fats. The
wavelengths of the microwaves will heat a few other materials but
with others, metals for example, they will cause sparking as
electricity is created instead of heat.
Maybe Metalwerx can tell us more about using refractory kilns in the
microwave so I do not blow up any more ovens.
Where can we get them even if it is only for experimental purpose?
(Watch for mushroom clouds over my house)
Perhaps Discovery TV could test it out in its urban myths sequence.
These guys are the geniuses who made diamonds in the backyard by
blowing up a barrel of fertilizer.
yes you can use microwaves for glass melting, PMC curing etc but is
does require making a little beehive kiln out of saffil and coating
the inside of that with carbon dag. You cant fire pot clay in it
though, the temperature maintenance and cooling times are impossible
to match. As I said previously, get it wrong and you will irradiate
yourself and that aint worth the price of secondhand test kiln.
I saw this little kit at a craft shop the other day that was a refractory kiln for glass fusing in the microwave. Pretty darned cool little concept, but I can't imagine how effective it might be. Or what it would make my food taste like the next time I wanted to use the microwave.
Quite a few years ago, when my kids were young, I bought for them a
kit that made plastic bugs from liquid plastic. They were called
Creepy Crawlers or something like that. Anyway, one Saturday they and
their friends made Creepy Crawlers all day. Later that night when I
tried to use the microwave to actually cook some food and it ran but
didn’t heat anything. I called the local appliance repair place and
they explained that microwave ovens are design to heat food and
liquids and by heating Creepy Crawlers I probably fried the magnetron
because the microwaves had no place to go. Replacing the magnetron at
that time was just about as expensive as buying a new microwave oven.
Then there were the teenage years with microwaved, flaming balls of
aluminum foil and “Let’s see what an egg does in the microwave”,
science experiments. I should have looked into buying microwave ovens
by the pallet. Now my kids ask me why I have so much gray hair in my
So moral of the story: Using your microwave oven for purposes other
than cooking can have unpredictable and expensive results.
Silversmith and Lapidary Artisan
Thank you but I think if Willis would be so kind as to give us the
source for the microwave kiln some of us could start there rather
than continuing experiments as I have done and we can compare notes
Maybe we could put saffil or coatings of clay outside and carbon
inside to improve on it and generate even higher temperatures inside
the kiln. Mushroom clouds over lots of houses!
BTW, I have posted on whether the extreme temperature and/or
pressure of ordinary extrusive/volcanic activity which is ubiquitous
here in BC could produce the “big 4” of gems (diamonds, rubies,
sapphires and emeralds). IMO, yes but the samples are so small how
can you do assays or RI tests? We have been prospecting a formation
beside a fault line where there is extreme glazing of stones (as in a
kiln?) and other evidence of past magmas. The geological maps
identify it primarily as amphibolite with micas and graphite. Could
the graphite become diamond? Amphibolite contains tremolite and
actinolite and as I understand it the combination of these with a
lot of compaction (from extrusive/volcanic activity for example)
gives nephrite jade.
What we have are some tiny samples of really stunning green
minerals. No jade I have ever seen can compare. Could this be
emerald? In some cases you put a sample under a 20x glass and you see
the even more intense green on a background of lighter green but even
then the super-green spots are barely visible. What size then? Maybe
1/1,000 mm? Can RI testing be done on that size?
This reminds me of what Rod the diamond driller posted once on the
BC Free Miners list. He had found stunning green crystals thousands
of feet down in a diamond drill core. He is still wondering what they
If anyone can tell me what tests they would run to determine the
identity of tiny (1/1,000 mm) green crystals on amphibolite host
rock I would be glad to put a gram of this grit in an envelope and
(gratis) send it anywhere on the planet. It is probably a more
mundane gemstone but then again…
Thank you but I think if Willis would be so kind as to give us the source for the microwave kiln some of us could start there rather than continuing experiments as I have done and we can compare notes on Orchid.
In considering what can happen in a microwave, take a look at this
(I found the Christmas lights especially fascinating):
Ahhh, youthful experimentation. During my first tour on Okinawa I
once put a huge cockroach in a microwave we had in our work area. I
then hit the Pastry button and watched. It started to expand, but
luckily the microwave stopped before it exploded. I think it ended
up about as large as the end of my little finger.
Lest you think me truly evil, I did place it in a glass with a plate
on top before it went into the microwave…
Mike DeBurgh, GJG
The kiln must be made of saffil, not used as a coating to clay. DO
NOT PUT CLAY IN THE MICROWAVE, IT IS EXPLOSIVELY DANGEROUS. Same
goes with carbon coating things, you have to have the right size kiln
to get the microwaves to reflect internally otherwise you are just
focussing them on a single part of the oven and that could be
potentially lethal (to oven and user)
I don’t want to think about the jewelry that didn’t get made while I
watched that turntable go around and around.
Thanks for the laughs and for the new way I have discovered to aid
and abet the skill of procrastination!!!
For those of you who missed the original link:
Ahhh, youthful experimentation. During my first tour on Okinawa I once put a huge cockroach in a microwave we had in our work area. I then hit the Pastry button and watched. It started to expand, but luckily the microwave stopped before it exploded. I think it ended up about as large as the end of my little finger. Lest you think me truly evil, I did place it in a glass with a plate on top before it went into the microwave..
Penelope and others at “Dirtbag Mining” lose much sleep considering
what will happen when Bin Laden and his gang of merry troglodites get
their hands on the microwave oven. Fortunately it takes a very long
extension cord to reach from the Kyber Pass to Baghdad.
Here is a free mining theory which may not be welcome on Orchid as
it is more field prospecting oriented than gemology oriented. But
maybe I can phrase it in terms which will satisfy both gemologists
and evil-doers who dream of microwave weapons of mass destruction. I
will out it forward as a science question in FIELD GEMOLOGY to
Discovery and K TV.
The Geological Survey of Canada maps we use say we dirtbaggers are
exploring close to major faulting. They also say we have
metamorphosed sedimentary and volcanic rocks here. This is in essence
a volcanic field. Some of these host rocks are clay family from the
ancient past and names like mudstone, shale, slate and argillite come
to mind. These are rich in colloidal minerals and other small and
nano-sized minerals with many economic uses. One of these is serving
as vectors pointing toward precious stones in the “big three” of
gemology, ie emeralds, ruby-sapphire and diamond.
IMO we can HAVE micro gems of all three here and I have the samples
now to prove or disprove it.
***** There seem to be gemologists from all over the “evil planet” on
Orchid so I will send 5 grams of grit in an envelope anywhere to
those who can make definitive determinations and that includes
gemologists in the Kyber Pass. *****
Willis kindly gave us http://www.pearsonsglass.com which tells us
how we can make a Biblical cockroach “Lake of Fire” right in the old
microwave. Cockroaches of the world, repent!
Waters near volcanic vents, pipes, fissures etc. whether eruptive or
not may see those lakes of magma fire heating the waters in a great
variety of cracks and pores in stones and I am amazed at the general
porosity of stones, after doing many porosity tests in studying
colloidal and colloidal-like minerals. Rocks are like sponges; pure
minerals less so. Does anyone know of a completely non-porous rock?
***** Does anyone know the porosity of kimberlite or other
kimberlite-like diamond-bearing rocks? How much air and how much
water is trapped in porous kimberlites? *****
Tairus in Russia claims to have produced not only hydrothermal
emeralds but also hydrothermal sapphire. Now we have samples of tiny
crystals here in BC which seem to be graphite and they match quite
well the graphite sample in the GSC kit of about 50 rock and 50
mineral specimens. But they are very small as are the “glassy” stones
in the same host rock. Likely the whitish to clear glassy stones are
quartz and calcite mainly.
Q 1 for Discovery amd K TV: Are some of these micro-crystals
The Urban Myths guys on Discovery blew up a barrel of fertilizer in
the backyard containing a handful of C and it turned to diamond. It
certainly contained air and maybe even some moisture. Who then can
tell me with absolute certainty that when lake of fire volcanoes
surface in our great outdoors microwave, the pressure combined with
the heat is insufficient to produce diamonds from graphite C? How
does it compare to the Discovery temp/pressure numbers?
Q2 - Likewise what about ruby-sapphire and emerald gems from
When the hydrothermal “colloidal minerals” and other micro-crystals
are deposited in assorted cracks in the rocks, cumulatively become
various “figurines” like abstract art cockroaches and then are
intensely heated and metamorphosed by thrusting of volcanoes,
earthquakes and the movemement of crustal plates as in
mountain-forming “subduction” here in BC, can anyone say with
certainty that the temperature-pressure which results is insufficient
to transform them into micro emeralds, ruby-sapphires and
diamonds… that it is less than that generated in the Discovery
So here is the bottom line:
***** IMO we have micro-minerals from of the precious gem “big
three” in our dirtbags from colloidal mineral exploration and that is
the reward of the last five years of hard work and many thousands of
hours in BC field gemology. *****
Dirtbag Mining Group
I’m sorry if this is a little late - I’m just catching up on the
Digest. If you are looking for a microwave kiln, you will find one
for a reasonable ( as kilns go) price at delphiglass.com, as well as
a tech support group who might be able to answer your questions
about its use.
Peter, it must come to the point at some time where one should say
"dont tell me, show me."
You have hypothesized about these diamonds and the like but you
offer no evidence. I have suggested a range of simple techniques for
separating these micro gems from the rest of the rock and offered
suggestions on then analyising your target minerals. Still you offer
us no evidence. It is time to either put up or shut up. Measurung
the porosity of kimberlite will not help you find diamonds in
regionally metamorphosed or hydrothermally mineralised rocks. I also
note that now you have added emeralds to your list which started off
with just diamonds and even then they would have had no practical
economic return. I can tell you how many angels can dance on a pin
head. As an Angel is a medieval gold coin weighing 6.8 grams, so when
you know the youngs elstic modulus of the steel the pin is made of
you can calculate how many angels- simple.