Looking for a Special Clay

Sorry for another post on the same topic, but I am hoping, by posting this after the holidays, that more will respond and help Sue M. out:

"I would like to find a clay that is weather durable. The project I want to do is to make markers for my herb garden and other garden plants... Any suggestions would be most welcome."

If you have some advice for Sue M., please take a moment to read the entire post and share your views.
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