Alisa og Claus Clausen on sun 10 feb 02
cone 6, ox.
Glaze test for: Saffire Blue, cone 6, ox.
All tests fired on white, iron flecked, mid-range stoneware.
Fired to cone 6 (1220c) in oxidation.
100c (212f) per hour to 600c (1112f)
150c (302f) per hour to 1100c (2012f)
100c per hour to 1220c (2228f)
15 - 30 minute soak depending on matts and glosses used.
cool down 100c per hour to 900c.
Natural cool down to 150c (approximately 15 hours)
42.6 Frit 3134
25.5 Custer Spar
2.1 Cobalt oxide
All raw materials measured up or down to nearest whole decimal.
Oxides used on percent basis to a 100 gram batch of glaze.
Forshammer feldspar for Custer.
Well covering light blue gloss, breaking darker blue with slightly greenish
cast. A lot of movement in glaze, but stayed where glazed. The thickest
areas are light to medium cornflower blue and the thinnest areas are dark
greenish in color.
Saffire Blue, revised by Ron Roy
37 Frit 3134
4 Strontium Carbonate
16 Custer Spar
2.5 Cobalt Carbonate
Forshammer Feldspar or Custer
a dark glue gloss that ran off the test tile.
Have to retest.
Regards from Alisa in Denmark