Sunday, 1 September 2019

Pennsic pottery achievements

I attend Pennsic again this year. I spent a lot of time hanging out at the Tudor House in the market place with Master Simon and all the amazing pottery people. I didn't help make the kiln this year as I was sleeping off a watch shift, but I was there for both firings. The first one didn't hit temperature. Master Simons thinks it might be because the woodbox tunnel roof sort of collapsed so it wasn't drawing properly. The collapsed part was dug out and the second firing went much better. The kiln was very crowded but everything seemed to come out generally fine.

I tried a new experiment this year. I was trying to make a quatrefoil cup because they have a very graceful form. I don't think I got the shape quite right though. It should cinch in under the foils slightly more. Then, not bad for my third ever item!

I did also try something a bit different with the glaze. I asked the blacksmith to crush up some malachite (copper carbonate ore) and some chrysocolla (copper oxide ore). I then mixed this with a clear glaze and applied it to the sides of my cup.

I now have a non-slip cup. It seems the chrysocolla had more gangue material (silica?) so left lumps on the side of the cup. The malachite, being a larger chunk of purer ore, turned into a finer powder so provided colour without texture. Very little copper is needed to achieve a good glaze.

I'm very happy with the outcome of this Pennsic and I'm looking forward to next time!
Left - malachite glaze; right - chrysocolla glaze.