Leaman Pottery Posted January 29, 2017 Report Share Posted January 29, 2017 Long ago I took a Glaze and Firing Course at a local Community College and learned about using Calgon Bath Beads to achieve a very lustery Mother of Pearl effect. Of course, after housrs of hunting through notes and the course manual (3 inches thick) I can't find the information. Does anyone know about this glazing method. Some brief Google searches only lead me to very expensive commercial glazes. Link to comment Share on other sites More sharing options...
Marcia Selsor Posted January 29, 2017 Report Share Posted January 29, 2017 the recipe may have needed to be deflocculated. Maybe they used the calgon beads for that.Calgon use to contain phosfates that worked.Today we use darvon 7 or liquid sodium silicate. So, good luck finding that recipe. Silver nitrate can make an etched mother of pearl when using it to fume an atmosphere.. Marcia Link to comment Share on other sites More sharing options...
Dick White Posted January 29, 2017 Report Share Posted January 29, 2017 Prior the mid-1980s, the active ingredient in Calgon water softener was sodium hexametaphosphate. In addition to its usage as a laundry aid, the sodium made it an excellent, readily available deflocculant for ceramic purposes (as well as agricultural soil testing). It was commonly listed in ceramic texts and instructional materials. However, due to environmental concerns (principally wastewater treatment and river pollution) phosphates have been generally banned from laundry products in the USA. Calgon was reformulated to use other chemicals to achieve its intended laundry result, but no longer functions as a deflocculant for ceramic purposes. As Marcia notes, we now use sodium silicate, Darvon, and to a lesser extent, soda ash for deflocculation. I don't know what the substitution ratio would be for old Calgon vs. any of these other deflocculants. Further, I wonder if some of that mother of pearl effect came from the phosphate content of the old Calgon? Link to comment Share on other sites More sharing options...
Mark C. Posted January 29, 2017 Report Share Posted January 29, 2017 Whats long ago?40 years 30 years -20 years-this may be as Dick says a long ago it worked and now it does not Like lead in gasoline -long ago they had it in all gas.Now its gone or paint and lead-long ago it was in most paints now its now. Mother of Pearl in my 44 years was a luster firing process -I still have a1/2 quart of it in a glass bottle. Link to comment Share on other sites More sharing options...
Magnolia Mud Research Posted January 29, 2017 Report Share Posted January 29, 2017 From the Leaman Pottery post :"... I ... learned about using Calgon Bath Beads to achieve a very lustery Mother of Pearl effect .... . Does anyone know about this glazing method"? My conclusion is that the Calgon beads were added as a major glaze ingredient, not as a deflocculant. Dick White posted: "Prior the mid-1980s, the active ingredient in Calgon water softener was sodium hexametaphosphate." If the Calgon beads were a major component in the glaze you should look for a commercial source of sodium hexametaphosphate (SHMP) [(NaPO3)6]. I regularly use Trisodium phosphate (TSP) [(Na3PO4)(H2O)12] as a glaze ingredient to add phosphorus to the melt -- up to 25 %wt in one glaze recipe. It is available as a paint remover and cleanser at most hardware, paint, and some grocery stores. As far as the glaze is concerned the difference between TSP and SHMP is in the sodium to phosphorus ratio. TSP has Na/P of 3 while SHMP has Na/P of 1. Phosphorus oxide is a network former (glass former) and also promotes the Mother of pearl (opalescence) effect in the glaze. The sodium that comes along with the phosphate is just more (R2O) 'flux' in the glaze. If I were going to try to produce glaze with an "MoP luster' glaze, I would start with a clear glaze I already have experience with and make a line blend test using say 2, 4, 8, 12, 16 pct phosphate to the recipe and see what happens. Assume the test glazes will run (probably won't) and protect the kiln shelf just in case! Concerning the floc-defloc:Both materials are water soluble and either can change the glaze slurry properties when used in 'trace' amounts. When TSP or SHMP is used as a significant ingredient to the glaze recipe proper, the concentrations are high enough that the floc-defloc issues are irrelevant. LT Link to comment Share on other sites More sharing options...
Mark C. Posted January 30, 2017 Report Share Posted January 30, 2017 If I recall the ads just call the Calagon Man and he should take care of it-Hey Calogon Man Mind you these ads where long ago. Link to comment Share on other sites More sharing options...
Marcia Selsor Posted January 30, 2017 Report Share Posted January 30, 2017 Isn't that Culligan Man? for Water treatment Marcia Link to comment Share on other sites More sharing options...
Mark C. Posted January 30, 2017 Report Share Posted January 30, 2017 Right you are Marcia It sounded to good to be true-just call and they luster your pots with mother of pearl-more like a Disney cartoon deal. Link to comment Share on other sites More sharing options...
neilestrick Posted January 30, 2017 Report Share Posted January 30, 2017 It was "Calgon take me away". Link to comment Share on other sites More sharing options...
Marcia Selsor Posted January 30, 2017 Report Share Posted January 30, 2017 I thought that was "Cowboy, take me away" - Dixie Chics I will be singing jingles today from Campbell soup to Wriggly chewing gum. Being alone with just the dogs and cats may create a lot of ear worms. Link to comment Share on other sites More sharing options...
jrgpots Posted January 31, 2017 Report Share Posted January 31, 2017 .... Silver nitrate can make an etched mother of pearl when using it to fume an atmosphere..MarciaSide track time, tell us how to use Silver nitrate for fuming. Do you have an example? Is it done in Saggar firing and at what temp? Jed Link to comment Share on other sites More sharing options...
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