Monday, November 28, 2011

Zach's Crystaline Cone 10 OX

Frit 3110     59.0
Zinc Oxide  24.6
Silica           15.90
Kaolin EPK  .50
+ Copper carb. 3.0
   Titanium Diox. 8.0

This recipe was fired to cone 10 oxidation, and I received great crystals, however cone 10 reduction does not allow crystal formation. Crazing does accour if not cooled long enough and it is not completely reliable for a stable glaze. The glaze is a glossy, iridescent one that will consistently form crystals when fired to cone 10 oxidation.

Sunday, November 27, 2011

Bob's Crystalline Cone 10 RE

FRIT 3110 58.1
Zinc Oxide 24.6
Silica 17.2
EPK 0.5

+ Copper Carb. 3%

Evaluation: This glaze is a clear gloss glaze that is prone to crazing and is not stable. Works best when applied thickly to avoid bubbling. The bubbling could be due to over-firing or under-firing. The glaze works well with colorants but has the best results with 3% copper carb. This gives a molted green and red surface. I believe the green areas are where crystals are forming and the red areas are places where the glaze was heavily reduced.

The glaze was mixed in 100g batches. The test tile was dipped, while the cup had the glaze poured on. Both were fired to cone 10 reduction in a gas kiln.

Bob's Majolica Cone 6 OX

FRIT 3124 26.0
Nepheline Syenite 23.0
Silica 20.2
EPK 17.0
Whiting 14.0

+ Zercopax 16.0

This glaze is a white opaque glossy glaze. It is very stable and works well for oxide painting on top of the glaze. The base glaze is Ron Roy's Majolica. His glaze tended to crawl and so I added 12% more Frit 3124 and subtracted 12% silica. It is important to apply thickly, and have a very clean surface to avoid crawling.

The glaze was mixed in 100g batches for the test tile. A 300g batch was made for the cup. Both tests were dipped. Bother were fired to cone 6 oxidation in an electric kiln.