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color tests for charcoal satin matt base, cone 6, oxidation.

updated fri 16 mar 01


Alisa og Claus Clausen on thu 15 mar 01

Color tests for Charcoal Satin Matt base, cone 6, oxidation.


Source: =20
Ceramics Monthy, September 2000
John Hesselberth, Ron Roy.
Derived from Tony Hansen's Matt Base.

Tested on light, iron flecked, mid-range stoneware, fired to 1215c, soak =
30 minutes, oxidation.

23.2 Wollastonite
31 3124
31 EPK
14 Flint

Subs. =20
Frit 169 for 3124
23 Wollastonite used instead of 23.2 grams.

Cobalt Oxide, Rutile, Tin oxide and Zircon (Zircopax).
Oxides are in precents to 100 gram batches of base.
All tests showed a gloss surface, some very fluid and streaking, but =
only one threatened to runoff the tile. All the others stayed above the =
bare margin of the test tile.

1 Cobalt oxide
Cobalt blue gloss, lighter than deep.

(2 Cobalt oxide, over looked)

1 Cobalt oxide, 5 Rutile
Brown ground with glueish green where thickest.

2 Cobalt oxide, 5 Rutile
Very fluid, but stable. Sreaky blues in a brown to black ground.=20
Very jazzy, looks like a dark version of peacock tail feathers.

1 Cobalt oxide, 1 Tin oxide
Grey blue gloss. =20

2 Cobalt oxide, 1 Tin oxide
Fluid but stable deep cobalt blue gloss.

1 Cobalt oxide, 5 Tin oxide
Cornflower blue goss where thickest, brownish where thinner.

2 Cobalt, 5 Tin oxide

1 Cobalt oxide, 10 Zircon
Deeper than above, but similar. Prefer above as blue in general
is softer, as tin will produce.

2 Colbalt oxide, 10 Zircon
Same shade as above but more fluid. Ran but stayed on the tile.

1 Cobalt oxide, 1 tin oxide, 5 Rutile
Very fluid and streaky but stable. Greyish blue ground with streaks of =
browns and temmoku blacks.

1 Copper oxide, 1 Cobalt oxide
Medium blue gloss, stable.

1 Copper oxide, 1 Cobalt oxide, 5 rutile
Green brown ground with blue streaking.

I am satisfied with these color tests, especially exciting were the =
tests with a lot of streaking and moving but stable on the tile. I =
personally liked the 1 cobalt, 5 tin blue the best, as it is a soft blue =
with toasty edges.

Best regards,
Alisa in Denmark =20