Is cheap clay okay to use?

Can I still use this clay?

• So about four years ago, I won 50 pounds of "sandy" clay in a school thing. I found someone who's willing to fire it (the teacher I'd known who'd given me the clay moved districts), and I'd like to use it. But it's been four years. The clay is pretty darn hard, but I can still slightly indent it with my finger. It's nothing fancy, just standard classroom (I think natural) clay. About the composition of the clay: "Blending clay is the heart of our business. We use the finest fireclays from Missouri, Ohio and California, ball clays from Kentucky and Tennessee, kaolins from Georgia, Florida and England, and stoneware clays from Ohio and Georgia, not to mention silica, feldspar, talc and grog. Our staff is in touch with technical personnel at mines around the country, and is always assessing new clays. All of our clay bodies are complex compositions, and we mix each one to a perfect, reliable consistency. That’s how we provide you with The Earth’s Best Clays." from the Highwater Clays website (http://www.highwaterclays.com/index.cfm?fuseaction=category.display&category_id=1 ) which is where the clay comes from, in case you need more details. Anyways, is there any chance of revitalizing it (if so, how?), or should I give up? I can give more details about the clay if needed.

• Answer:

  If you can just barely dent it, it is going to be very hard to break up to quickly soften, but if you put it in a couple of thick plastic bags or a container like a trash container you can seal, you can add water and let it stand for a while - days to weeks. When I am doing it on a smaller scale, I use Rubber Maid Tough Totes, which seal tightly and I add the water using a wet old towel so I can drape it over the lump instead of having the water puddle on the bottom, turning it squishy. If you can cut it into lumps, it will moisten faster.