The technique is basically making quick and easy rubble that can be applied to the bases of models and terrain pieces and so forth. There's a video some dude made up on You Tube that will also prove to be a useful reference point. Some of the "ingredients" that he used, I've changed either for convenience, or because it isn't readily available in the UK.
Anyway, here's a list of what I used, the pictures below are a rough reference guide:
Corroded iron flakes from an old metal plant pot
Crushed snail shells (no snails harmed by me, I just used what the local birds left behind)
Some small ready made bricks (available from Ebay or most model shops)
Chopped up straight bits of sprue (get rid of any with writing on, or those round bits)
Cork chunks (available from Ebay or most model shops)
Sand (use about an equal proportion to the total volume of everything else)
Mix all the above together in a plastic pot or whatever else you have laying around. I'd advise against using your best china for obvious reasons.
To this, then add a decent spoonful of PVA glue. Paint should now be mixed in until the mixture is fully paste-like (the video reckoned to use black, but I ran out so I threw in some grey).
And the pictures:
|Mix of crushed snail shell and metal flakes|
|Chopped up sprue|
|All mixed in a pot. With sand.|
|Add PVA, and then add paint to point of saturation.|
|Apply with the spoon. Don't use your best spoon.|
|You used your best spoon didn't you?|
|Scatter more bits of sprue on top and press in if you want.|
|Once you've sprayed this lot, and drybrushed it, in theory it will look proper good, according to the internet.|