Hi
I'm trying to learn how to do mocha diffusion. I read your description along with a number of others on the web. However, I'm not having any luck getting the dendrite pattern. I will try very a lot of things and nothing seems to make much difference.

This is what I've tried:

1. Slip made of Tennessee ball clay
2. Robin Hopper's diffusion slip: (ball 75, spar 5, silica 10, epk 10) plus I add 5 3134 and 10 RIO
3. adding hardwood ash, or sodium silicate, or Calcium nitrite to the above slips

I've used thick and thin solutions of cobalt carbonate and ordinary vinegar or apple cider vinegar.

I've tried using in both horizontally and vertically on my leather hard G6 mix clay.

The very best I've done is to get some almost microscopic dendrites on the edge of my dribbles.

Also, in a CAD article Robin Hopper gives the following recipe  for diffusion slip

ball clay   75,

Feldsspar  5,

silica       10,

Kaolin      10

Does anyone know what kind of ball clay and feldspar one should use?

I would appreciate any advice or guidance you can give me in debugging this.

Thanks

Larry