What causes pinholes on my glazed bowl? I used Amaco glaze ironstone, fired to cone 5 in the sitter, cone 6 barely bent, so i didnt overfire.

Question:
Pinholes! All my extruded vases cracked in glaze fire in the valleys of the die.

Answer:
Gosh that's a tough one to answer. Could be a lot of things. Could be dust on your bisque ware, could be you need to soak your glaze firing for longer at max heat, could be an issue with the glaze itself.

That's probably not a ton of help, but glazing is complicated and I'm definitely no expert on trouble shooting. I'm pretty uncreative with my glazes. My goal is usually just to not ruin my nicely thrown pot with the glaze:/

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