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Add Water to Make the Plaster

Plaster turns into clay after water is added.
Copyright Lee Wallender - Licensed to About.com
Next step is to add a nominal amount of water to the dry plaster mixture, until it turns into a thick, heavy clay. While I did this on a small scale, and found it easy to do, I can imagine that it's a beast when you're dealing with fifty pound bags. My only parallel is concrete. A mortal human finds it exceedingly difficult to mix up an entire bag of concrete in one mix. So, you need to halve the bag. I imagine you would need to do the same thing with these 50 lb. American Clay bags.