Albany slip, how I miss you!
I have this great recipe out of the Watershed glaze book: the best $25 I ever spent. It goes like this:
Albany Slip 35.87
Gerstley Borate 3.26
Custer Spar 21.74
Yellow Ochre 7.61
I looooved this glaze. In its original form, it's a warm buckwheat honey color, breaking to red where extremely thin. The gem jar pictured above is glazed in Amber Celadon, in its original, Albany-slip form. I tried the commonly recommended substitute for Albany slip, Alberta Slip, but the results were disappointing: a perfectly nice olive color (NOT amber) marred by alot of scumming. In truth I have found Alberta to be an inadequate substitute on other occasions as well. It appears to be noticeably more refractory than Albany, and often creates glazes that, while nice enough, are quite different than the ones they are meant to duplicate. So, boo, too-bad-so-sad, no amber celadon for Lori, right?
Not so fast!
My husband the genius had a typically briliant idea. We live in Maine, where we are surrounded by marine clay. It's an fine-particled earthenware, not great as a body clay, although some potters use it. (Doug and I memorably spent our camping honeymoon building tiny, duelling kilns out of available materials -- sand, rocks, stick, clay -- to fire a few pinch pots and figurines we'd made from it.) By itself it makes an extremely runny (at ▴10) slip glaze, dark brown. We decided to try it as a substitute for Albany slip.
Now here's where I run into trouble. We made two versions, the first a one-for-one substitution, the second leaving out the yellow ochre. One of them was exactly perfect, the other was nice, no scumming, but olive rather than amber.
I can't remember for sure which was which. I think the one-for-one was the success, but Doug points out, why would we have tried the second way, if the first was perfect? (Answer: because he is always trying things just for the hell of it. Not that there is anything wrong with that.) Anyway, it's time to find out, once and for all: I have made up a 1000 gram batch of Amber Celadon, using dried & pulverized local clay as a direct substitute for Albany slip clay. If this works, I can see using local clay as a substitute in many recipes; Albany slip problem solved! it's a bit of a hassle, of course, to go collect it, slake it, strain out all the little rocks and sticks and insect bits, then dry and pulverize it; but worth every step if I can regain that yummy look.
Will let you know after Sunday's firing how this works out.