Friday, February 8, 2013

Glaze excavated in your backyard

Clay glaze is kind of earthly topping for your work. The beauty of those is not only that they are everywhere (meaning all over the globe), but also they are quite easy to find, processed and used. Most of clay glazes will be based and colored by Iron (most common element (by mass) forming the planet Earth as a whole), so the regular colors of clay glaze will be browns and green. Sometimes you will get black, blue, yellow green and any number of colors depending on which oxides are present in your clay glaze. Now I just hear it - but most of them are boring brown. Than first of all there is never boring brown, but encase you are not those brown loving enthusiast (potters know that brown has about thousand shades) let me show you, what little fun with clay glaze can do.

This summer on our glaze classes we conducted small experiment as a process of understanding glaze behavior and clay glazes and as a kind of jumpstart test when you want to adjust your clay glaze. Notice how glaze change with the clay type

The base for our test was clay glaze found, when our friends builded home in Obřany. Here applied on technical porcelain by itself.


With above clay glaze we made test as follows:
Clay glaze Obřany 200 - calcium carbonate 40




Clay glaze Obřany 200 - calcium carbonate 40 - Titanium dioxide 20




Clay glaze Obřany 200 - calcium carbonate 40 - Titanium dioxide 20 - Soda feldspar (Ž55NaK60) 30





Clay glaze Obřany 200 - calcium carbonate 40 - Titanium dioxide 20 - Soda feldspar (Ž55NaK60) 30 - Cobalt carbonate 4




To see even more results we started second test as folow:
Clay glaze Obřany 200 - Ash glaze (mixed wood ash glaze) 60






Clay glaze Obřany 200 - Ash glaze (mixed wood ash glaze) 60 - Zinc oxide 30






Clay glaze Obřany 200 - Ash glaze (mixed wood ash glaze) 60 - Zinc oxide 30 - Strontium 40 - Copper carbonate 5




So next time you go for a trip in nature do not forget bag and small spade, just in case...