This stunning crackle effect is created by painting slip (with added sodium silicate) on the outside of a newly-thrown narrow cylindrical pot. This is gently dried with a blowtorch so that the outer layer cracks as the pot is stretched into a pleasing rounded shape. This is a particularly challenging technique, as the potter can't touch the outside of the pot as it is stretched, because that would eliminate the texture. There is also no opportunity to trim and refine the pot once thrown, which means the walls of these pots tend to be thicker than traditionally thrown and trimmed pots, making them a little heavier and more substantial.
 
The bump rim on this pot was formed after throwing, by pressing a ball-shaped tool under the rim, which then needs to be re-rounded. The bumps perfectly emphasise the crackle effect.