Dendritic Mocha Diffusion

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Has anyone tried the Dendritic Mocha Diffusion technique with just an oxide/water solution instead of an acid/color mix recipe?

Yes, I'm looking for an easier, softer way and will get around to a test tile soon but curious now. :-)

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Guess I should add I'm looking at this from a drip application. Seems there is more to the technique that just that. :-)

 

This type of application. 

 

[PeterH]

Most of the impressive mocha videos I've seen -- like this one -- seem to use a slip which stays wet for a very long time. 

Is this peoples practical experience? And how do you stop the slip from drying too quickly?

PS
Physicists call this viscous fingering (or more formally Saffman-Taylor instability).   There seems strong evidence that changes to the rheology (viscosity, sheer thickening/thinning, etc) of the liquids can have major effects on the nature of the fingering, so additives  may be important.

Abstract of a paper Viscous fingering in complex fluids
https://iopscience.iop.org/article/10.1088/0953-8984/12/8A/366/pdf

More rambling background paper Controlling Viscous Fingering
https://www.europhysicsnews.org/articles/epn/pdf/1999/03/epn19993003p77.pdf

[Min]

The dendritic patterning is formed when the acidic "tea" made from a mild acid + colourants reacts with the alkaline slip. If you use just water then you won't get this reaction. It may spread a bit but I think that's about it. 

I used a mocha diffusion technique for quite a few years, to get a softened look to the patterning I used a white opacified glaze overtop of the cobalt and manganese diffusion. In order to get the most diffusion the clay needs to be as wet leatherhard as possible and you need to work quickly getting the tea onto it. Even using a clear glaze can soften the patterning, especially if it's a fluid glaze.

One of my old pots using mocha diffusion, I didn't dip the pots in slip I used a slip trailer and splatted it on. The slip is actually just ^5 B-mix plus red iron oxide, it goes gray under the white glaze. Hoppers slip recipe works well too. Adding a drop of washing up liquid to a couple tablespoons of the tea benefits the reaction of the patterning.