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fw: re: is terra sig available commercially or must it always be

updated sun 27 mar 05


Vince Pitelka on sat 26 mar 05


Rob -
I don't know of any commercial sources of a terra sig that is worth the
money. You can find my article on terra sigillata at

This method really is not nearly as complicated as it first sounds, and it
definitely makes a superior terra sig. If you use this method, you will
need to purchase a hydrometer that measures specific gravity. You can get
an excellent one for a very reasonable price at the Sargent Welch website.
The website follows, and be sure to paste in the whole website with all the
underscores but with no open spaces: one specified "WLS42035-A" is the right one - it has a specific gravityrange from 1.000 to 1.2220, which is exactly the range you need for terrasig. A normal glaze hydrometer purchased from a ceramic supplier does nothave nearly the sensitivity, and will not work well for terra sig.As you can see, the price of $10.25 is very reasonable, but theseinstruments are very delicate, so I would purchase at least two. When Ibought my first glaze hydrometer thirty years ago, I only got one, and itbroke on the third or fourth use. I didn't realize how fragile they are.Next time I bought two, and had them both for many years.Good luck -- VinceVince PitelkaAppalachian Center for Craft, Tennessee Technological UniversitySmithville TN 37166, 615/597-6801, wpitelka@tntech.edu