I've been scouring my single player map for clay, just out of force of habit. I've strayed a long way from home... Many, many days of walking and sailing. My inventory filled up, and there was nothing I could really get rid of. So, I decided to furnace that clay and put it in bricks for compact storage.
http://img375.imageshack.us/img375/2151/26314004.png Been slowly deforesting the island to keep my furnaces going
http://img375.imageshack.us/img375/2151/26314004.png Been slowly deforesting the island to keep my furnaces going
You can compact the clay into clay blocks without turning it into bricks though.