search  current discussion  categories  glazes - cone 4-7 

glaze test for cone 6 marcie's matt, ron roy revision

updated mon 7 aug 00


Alisa and Claus Clausen on sun 6 aug 00

Tested on a light grey mid range stoneware, fired to cone 6 oxidation.

The original recipe is as follows:
23 EPK
20 Dolomite
38 Neph. syn.
18 Silica
4 Whiting
10 Gerstely Borate
Described as a semi matt for cone 6 reduction. I fired it oxidation and =
either cooled the kiln too fast, resulting in only this glaze of the =
many tests, to craze. On further testing and slower cooling, I =
experienced no immediate or delayed crazing (over 14 days now since =
test). However, I have retested it with Ron Roys revison that lowers =
the expansion/contraction.
Revised receipe for Marica Selsor's Matt.
15 Frit 3134
13 Neph Syn
14 G200 spar
24 Dolomite
32 EPk
2.0 Silica
Substituted Frit 3134 with my local frit MOK 623, and substituted G200 =
spar for my local Forshammer spar.
Results were clean, good, semi matt. Did not craze. =20
I dipped half a cup in the original receipe and the other half in the =
revised formula. Cannot see any difference in glazes.
Overall surface on convex surface is smooth, but there are differences =
from matt to fairly glossy, and milky and glossy where thickest. Inside =
of cup is a consistent, smooth gloss.
Thank you Roy for the revision. I would like to add that although the =
glaze above functions fine, I am using your Satin Matt,
instead either version. Ron Roy's satin matt has an excellent hard and =
smooth surface, nice to the touch (maybe even stick free for =
casseroles?) that it suitable for many uses. I use it now as a basic =
clear, over engobes and for insides of cups and bowls. I have adopted =
it as my standard clear in the workshop.
Best regards,
Alisa in Denmark
PS Roy, as soon as I get some talc, I will send results of your =
revision for Cream Gloss. Thank you.