I've finally found my blue! Some other vapor firing potters out there may be thinking I speak heresy but at least it's an ash glaze, right? I've been trying to find a soft blue for some time now. I've tried several ways to get it without using cobalt but between the iron in the ash and in the clay that clearly wasn't going to work(though it does hold some promise on porcelain.) The other problem I encountered was that I only needed fractions of a percent when using cobalt and when you're mixing 100gram test batches that is not so easy or accurate. My solution was to mix up a 10000 gram batch(5gal bucket) and start with 1/10%(10g) cobalt and that was spot on the first time. The only drawback is that cobalt is so powerful it eliminates many of those little variations you get in an ash glaze. It usually likes to break brown on a sharp edge and I'm not seeing that happen, perhaps they're just not any edges sharp enough on this piece. Who knows what this will do in the wood kiln.