An interesting topic from conversations on the hotglass list and additional information
"OK - I know there are paperweight and marble makers out there. A "sulphide" as I have always understood it - is actually a type of ceramic, cast and fired - and then encased in glass.
Does anyone KNOW what type of ceramic this is? Porcelain type perhaps?
does anyone have a "sulphide" recipe?
dying of curiosity...."
Cheryl - www.dragonbeads.com
This recipe comes to me from Roland Butler in issue #5 of Independent
Potash Feldspar 17.6oz
Edgers plastic kaolin 34.8oz
Potters flint 8.0oz
Ball clay 2.6oz
Mix dry and then add enough water to make a plastic putty. Air dry tnd then
fire to cone 5 (2200f)
I haven't tried the recipe so I don't know how it works. It's supposed to have an LEC of 95
St.Clair Paperweight - image of the famous American Indian Tecumseh.
the COE of the sulphide has to match the glass pretty closely - or the glass and sulphide will separate - and the whole piece will crack.
-Cheryl - www.dragonbeads.com
I was recently asked to research how paper weight sulphides were made and although paper weights are not my area of expertise I remembered my friend Paul Stankard had done some research in the area when we were at Pilchuck some years ago. Paul was very happy to share his findings. I thought posting it on this site would be a good place for sharing those findings. I'll also post it on my web site.
White Sulphide Inclusion for paper weights
80 % SiO2 200 mesh
20 % crystal fine powder, same glass as being used. 100 to 200 mesh preferable. Grind in a morter and pestle and mix throughly with the silica.
For color add Paradise Paints or Kugler color.
Procedure for preparation: Add enough Gum Arabic solution to make a moldable paste. Press paste into mold and allow to almost dry. While still a bit moist but easily handled remove from mold and put in kiln. Fire to cherry red and cool. When cool remove from kiln and clean any areas that need enhancing. The "sulfide" will not be brittle as the glass will have fused the piece together. After cleaning put into pick-up oven and reheat to cherry red once again. It is now ready to be encapsulated in weight.
The directions for making the "sulfide" was told to me by Paul Stankard. He along with Dwight Lanman did the experiments at Pilchuck some years ago.
Back to FAQ