[Fuad]

Hi everyone,

Has anyone ever fired gemstones (semi-precious or low grade precious) into their work?

I was thinking that natural stones might have inclusions that might cause the gem to explode. So that brings me to my next idea - using man made synthetic stones. Would that work?

Does anyone know what cone these stones can withstand and still adhere to the glaze?

I'm not opposed to the idea of the stones melting and creating interesting effects... I just dont want big black blobs all over my work.

Thanks!

[Matt Oz]

Here is a thread from the clayart archives, that may be helpful.

gemstones and ceramics

[INYA]

Please let us know what you will find out!

very interesting idea...

[trina]

Hi there,


There are lots of natural red garnets where I live. I find them from time to time, i have tried to fire them, Low fire 1000C, they don't explode but they do turn black. The heat must change them in some way as polishing ect doesn't change them back. I have seen some artists firing stones with silver clay or those type of products at around 700C, haven't tried it myself so don't know for sure how it works. T

[Amy Waller]

Here's a link to a forum thread that has some useful information.

There's a link to a chart about firing gemstones in that thread, but it doesn't seem to be active. Here's a link to another chart with information about firing gemstones with precious metal clay.

Good luck!

[Antoinette]

Since the 70's I' ve fired beach sand with pebbles up to about 1/4" using clear glaze to place the sand/pebbles at low fire cone 04 and cone 6 and have never had issues of explosions, crazing or cracking. Actually the firing burns off the impurities/oxidation on the pebbles making whatever color of the pebbles more brilliant. I've gotten my sand/pebble mixture from New England beaches so the composition is primarily black, pink, and white granite.

To your point, based on my successes to date, I just recently tried firing semi- precious stones I got at a rock mineral store in AZ as well as petrified wood pieces - not so good results! At cone 6 placed using clear glaze, I got the results in the thread provided in the first response. Since the gems used were silica-based crystal structure, they all turned white! No explosions,crazing or cracking occurred though. So after a discussion with an engineer who works in the coatings business, I was going to try again, this time with a raku firing- lower temp. and very short firing. Again, in reading the threads, this might work...

[INYA]

Antoinette, on 19 May 2012 - 12:19 AM, said:

Since the 70's I' ve fired beach sand with pebbles up to about 1/4" using clear glaze to place the sand/pebbles at low fire cone 04 and cone 6 and have never had issues of explosions, crazing or cracking. Actually the firing burns off the impurities/oxidation on the pebbles making whatever color of the pebbles more brilliant. I've gotten my sand/pebble mixture from New England beaches so the composition is primarily black, pink, and white granite.

To your point, based on my successes to date, I just recently tried firing semi- precious stones I got at a rock mineral store in AZ as well as petrified wood pieces - not so good results! At cone 6 placed using clear glaze, I got the results in the thread provided in the first response. Since the gems used were silica-based crystal structure, they all turned white! No explosions,crazing or cracking occurred though. So after a discussion with an engineer who works in the coatings business, I was going to try again, this time with a raku firing- lower temp. and very short firing. Again, in reading the threads, this might work...

That sounds really interesting!
Do you have a picture maybe?
Did you spray the glaze?
Thanks!

[Fuad]

This sounds very cool Antoinette!

I've heard about stones turning opaque and white - and it's not something I'm against happening - but are they more delicate? do they crumble? Do they look just plain ugly?

I would love to see some pics of your successes and attempts!

Antoinette, on 18 May 2012 - 06:19 PM, said:

Since the 70's I' ve fired beach sand with pebbles up to about 1/4" using clear glaze to place the sand/pebbles at low fire cone 04 and cone 6 and have never had issues of explosions, crazing or cracking. Actually the firing burns off the impurities/oxidation on the pebbles making whatever color of the pebbles more brilliant. I've gotten my sand/pebble mixture from New England beaches so the composition is primarily black, pink, and white granite.

To your point, based on my successes to date, I just recently tried firing semi- precious stones I got at a rock mineral store in AZ as well as petrified wood pieces - not so good results! At cone 6 placed using clear glaze, I got the results in the thread provided in the first response. Since the gems used were silica-based crystal structure, they all turned white! No explosions,crazing or cracking occurred though. So after a discussion with an engineer who works in the coatings business, I was going to try again, this time with a raku firing- lower temp. and very short firing. Again, in reading the threads, this might work...

[Lucille Oka]

There are lots of places to get gemstones, tumbled stones, geodes and pure ores. One place in Arizona I think the name is 'T-Rocks' or 'All In Vein' I am not sure of the name it is near Carl's Jr at 1451 West Main Street in Quartzsite, AZ.
There are semi-precious stone stores in the mall in Tempe, and in stores in Scottsdale. You can also get them at "Beads Galore" in Tempe, AZ.