In 2010 I painted this Space Marine Statue from the Honored Imperium set. I decided to use it as an opportunity to experiment with marbling effects - something that I'd learned about but never really tried previously.
This week I got an e-mail asking me how I'd done it. Three and a half years later I had a hard time remembering. Luckily, I'd written my recipe down in a forum so I just needed to figure out which one.
Since I went through all of that effort, I thought it would be worthwhile to repeat that recipe here:
I started with black primer. Then, I took a little P3 Troll Base color mixed with Liquitex Gloss Medium and a bit of water at about 1:2 - making it a little transparent. This was applied directly to the black with a small sea sponge. I dabbed the whole thing once, let it dry a bit, dabbed in again, let it dry, and on and on until the color built up. The trick seems to be to keep the paint from smearing too much. Once the base was where I wanted it then the fun part started. That is, painting the veins of color. I added a lot of the troll belly color to the existing color to lighten it up. Then, I painted the veins in with a feather rather than a brush. Why? Because the feather will naturally move around as you paint with it keeping the cracks much more natural in appearance. I had done a Google image search to get a sense for how the veins should look so I tended to keep them flowing in the same direction - but obviously they don't all go the same way. If any of the veins looked too pronounced then I would either dab them with my finger to blend out the line or I would do it with a brush. When that was done, I went back over a few of the veins with a brush to add a bit more emphasis to them. At that point I was pretty much done... with the statue anyway. The base is pretty straight forward.
BTW - That feather technique is something that I learned about when I was a Set Painter for television. I wasn't sure it would translate to small scale, but it seems to work just fine. It did require trimming up a feather to get a useful tool out of it, though. I really need to do a video on this subject...