Techno Tip Changing the Firing Temperature continued from pape Some Other Points If the cone 10 glaze is a stoncy matte and is not melting enough, then to duplicate it faithfully | guess you have to make a cone 6 glaze that is not really melting enough either. However this is certainly mot advis- able for functional ware. You will want to fire tests to compare the degree of melting (consider using a flow tester). Be sure to try the glaze in thick and thin layers and watch for crazing. Different minerals release their oxides to the melt at different temperatures, even though they might have similar chemis- tries (for example wollastonite and whit- ing both contribute CaO yet the latter requires a higher temperature to release it to the melt). To take some common cone 10 glazes to come 6: * White matte: Just opacify a matte base glaze using Zircopax or tin oxide. * Tenmoku; Use high iron in a fluid base. However you will not get the same light brown crystal lines on the edges of con- tours and it will crystallize a yellowish colour if cooled too slowly. * Robins ege blue: Add a little cobalt and rutile 10 a matte base, * Black; Adda black stain toaclear glossy Blaze. * Purple/Lavender: Use a high magnesia base clear (use Prot 3249 of Fusion Fo? to source the MoO; MgO sourcing raw mate- nals won't melt at cone 6) and add cobalt carbonate or oxide (or a blue stain) around 1% and adjust as needed. * Celadon; Add a green celadon stain to your clear base. * Oatmeal/Cream: Add some iron, a light brown stain or rutile (rutile will also vari- egate it), Add a bith Zircopas to opacify if necessary (to bring owt the pastel shade). Tony Hansen The Techno Tip column is generousty spon- sored by Plainsman Clays Limited in Medicine Nar, Alberta, and fir affliliates in British Co- lunbia, Greenbaum Potters Supply Lid, and Vancouver Island Potters Supply. 10 Beyond Borders A Craft Marketing Conference www.ksac.bcbca S86 Opposite page Keynote speaker: Alan Elder, Curator of Canadian Crafts, Decorative Arts and Design at the Canadian Museum of Civi- lization in Ortawa, Slide presentations and discussion: Irene Frolic, Glass; Thomas Mann, Metal/ Jewelry; Jonathan Simons, Wood; Joanna Staniszkis, Fibre; & Diane Sullivan, Clay. Panel discussions and workshops focus on topics: Pricing: Working with Galleries; Internet, Wholesale va. Retail Shows, De- veloping A Profile; Photography and Exporting to the US. See website for com- plete list of speakers, Representatives from the BC Arts Coun- cil, Canada Council, Department of For- cign Affairs & International Trade and Trade Routes have been invited to partici- pate in a Finding Funding panel! To add your name to the conference mail- ing list, email or call 250.352.2914 Extension 49. For Sale Teaching/drop-in Studio Profitable Great opportunity for pottery teacher(s) Fabulous waterfront location in Vancouver Call for more information Ask for Dave 604.270.4244 Tuesday through Friday Saturday Vancouver island Potters Supply Serving all of Vancouver Island and the Gulf Islands New Hours 10 minutes south of Nanaimo #5, 2071 South Wellington Road, Nanaimo, BC Phone: 250.716.9966 Fax: 250.716.9960 9:00AM to 4:00PM 9:00AM to 2:00PM Potters Guild of Bntish Columbia Newsletter February 2003