Cracked finish pots are quickly becoming a favorite of bonsai enthusiast. A pot is shaped and then exterior is painted with a generous coat of sodium silicate.  The silicate is then dried with a torch.  Next, the pot is stretched into the final shape producing a cracked finish of the surface.  The cracks are a finish only to the surface so the integrity of the pot is not compromised.  Generally, cracked finished pots are left unglazed and a very attractive option for conifer trees.