lava rocks

Marianne Stebenne

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Mar 23, 2002, 10:49:36 PM3/23/02

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thought i would place some lava chunks in pieces that i made........

so i went to the hardware store and bought a bag...... you know the chunks
you place in your gas grill for bbq'ing.....

well since this stuff is man made....... it melted.... actually a nice
shiney brown in a cone 10 reduction........

just thought i would inform the group......

does anyone happen to live near a volcano so that i can get little chunks of
real lava????? saw this a while back when i visited iceland........
nice effects when no melting...........

thanks in advance........ and feel free to email me direct

marianne stebenne

--
marianne stebenne
Pottery Artist

"I Touch the Earth the Earth Touches me"

http://web.meganet.net/mstebenn/

Mike D

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Mar 24, 2002, 4:44:41 AM3/24/02

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Hi Marianne,

I live on a volcano here in New Zealand, called One Tree Hill or
Maungakeikei in Maori. I too have tried firing lava and scoria
and both melt at quite low temperatures (softening at 1000C).
I guess, when you think of it, lava flows out of a volcano
at a bright red to orange colour, which is about 1000/1100C.

The pottery from Iceland sounds as though it may have been
refired at low temperature after the initial 'finish' firing.

Cheers, Mike Donaldson.

Brad Sondahl

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Mar 24, 2002, 10:25:53 AM3/24/02

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It's fun to play with adding rocks to pottery. When I've tried it I've used
round rocks for knobs, set on the glazed lid. Unfortunately they are pretty
unpredictable as to which melt, especially at stoneware temperatures. Quartz
remains unchanged, but may crack out of the glaze in cooling.
Brad Sondahl
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http://home.earthlink.net/~bsondahl/
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rms

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Mar 25, 2002, 11:46:03 AM3/25/02

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In article <3C9DEF9D...@earthlink.net>, bson...@earthlink.net says...

>
>It's fun to play with adding rocks to pottery. When I've tried it I've used
>round rocks for knobs, set on the glazed lid. Unfortunately they are pretty
>unpredictable as to which melt, especially at stoneware temperatures. Quartz
>remains unchanged, but may crack out of the glaze in cooling.
>Brad Sondahl

There are slags from steelmaking that melt at 1600C and above.
Slags vary greatly depending on the method and mixture but high
temp slags are out there. It looks like lava rock.

Here is a link that has more than I want to know about slag:
http://www.bergsmannen.se/english/eng_jitang.htm

I lived in a house covered with slag once. Good insulation. rms

James Aberle

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Mar 28, 2002, 8:30:50 PM3/28/02

to Brad Sondahl

I love to experiment with design in my pots ..and am always learning...i love the
idea of lava rocks...but won't a rock explode in the kiln or does it depend on
what type of rock........pottery jim in NJ

Marianne Stebenne

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Mar 28, 2002, 9:09:12 PM3/28/02

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i have fired several small pieces of rocks from my personal collection
inside of my work.......

some shrink

some leave residue

and some stay in place and become piece of the clay.....

i have never even thought of the rocks exploding.....

so far i have fired: malacite, a few various forms of crystal,
calcite, amethyst, citrine, herikimer diamonds...... to name a few.....

all with informative results....

good luck in any endeavors you try: )

marianne
"James Aberle" <jab...@monmouth.com> wrote in message
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