Glaze Tests by Karl Martz, 1970s-1990s.

Throughout his career, Karl was fascinated by glazes, building on his B.A. in Chemistry (1933). At all stages of his career, he continuously tested glaze formulas, keeping extensive records in notebooks. From 1952-1968 he published over a dozen articles on glaze formulas and techniques in Ceramics Monthly. Dozens of glaze tests can be seen in Karl's Pink House Shop. See also Glaze Test Tumbler.

Selected for being attractively colorful, the glaze tests shown on this page are a small subset of what was in Karl's studio when he closed it in 1996, shortly before he died. The holes in the tops and bottoms enabled the tests to be hung in stacks on ropes.

Below is a 2004 photo of Becky (age 90) wearing a necklace of miniature glaze tests made by a former student of Karl's. Regrettably, Eric no longer remembers who made this necklace. Possibilities include June Kapos or Deborah Gray (see friends).