Potters & Sculptors - Making Rock from Mud
Numerous members have used SCM and Jen's Juicy Fruit with excellent results. I believe the crystals being objected to are some kind of crystal that is growing in the melt upon cooling, not unmelted strontium poking out of the matrix. The crystals have sharp diamond reflective points which would not be present if they had been even slightly attacked by the glaze fluxes, of which there are plenty, evidenced by the fact that the glaze is very prone to running.
My understanding is that Catherine Rehbein uses commercial glazes, not SCM,
I had the same kind of crystals form in pots fired to cone 9 both reduction and oxidation at the a Steven Hill workshop in 2009.
You can render your rough pots smooth as a baby's bottom with about ten minutes of sanding with 200 and then 400 grit carborundum wet sandpaper, but the sparkly effect will be gone.
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