The spiral here is depicted as a snake coil. The snake, in Neolithis times was symbolic of life force. It wasn't the body of the snake that was sacred, but the energy exuded by this spiraling or coiling creature which transcends it's boundaries and influences the surrounding world. The height of the "snake theme" was around 5000-4000 B.C. The spirals from carvings in Scotland around that time.
-hand built, carved and soda fired