I thought you had said that your clay was in a container that didn't
allow you much access to removing it. You might try my method. I have
a very long screwdriver which I force almost to the bottom of the clay
making multiple holes. The dryer the clay, the more holes. Fill the
holes with water and let set a few days. I do this with my bicks
standing on end. Some have been unworkably dry but were reconstituted
in this manner. Leather hard, though? I doubt it. Can't hurt to try.
Catherine in hot Yuma, AZ