How can i make mud that looks like this

Hi Little nick.
Attached is thread from Stockholms IPMS homepage, where the builder ... Anders Isaksson..has explained his method. Anders is an excellent modeller and has written articles for quite a few magazines! I have included a rough translation of his explanation. I have seen this at one of the meetings around this time and it is a classic. He won a medal (cant remember what) at euromilitaire with this. It is built OOB.

"The mud is a mixture of pigment powder and Liquitex Texture Gel. This comes in a few different variants and the one I used here is called Ceramic Stucco. Look like a normal gel medium but is very fine.
So as not to make the mud too uniform I have used assorted old brushes and an old toothbrush.
Finally I blended some pigment with tamiya thinner and airbrushed the bottom region to tie it all together. then I reworked little bits with a dry brush to make run marks.
I experimented a little with wet and dry muds ... it looked OK in reality but horrible in photgraphs, so I kept it all dry."

When asked where to buy the Liquitex Texture Gel, he replied any good art or paint shop and includes some pictures of the bottles.