Another technique I have come across over the years is to use faceting to create interesting and organic textures.
As depicted in the video to the right, I start by stretching springs to create wiggle-wires. I then use these wires to facet the cylinder. Next, I stretch the bowl outwards by pushing on the inside while holding the rim firmly.
In effect, the speed of the rim is slower than that of the base, so the grooves towards the base move faster than the top and the grooves are twisted.
Artist: Mark Peters, website: http://www.pinerootpottery.com/