I had to add a rock wall where the track cuts through the ridge.

For this project I used Hydrocal, which is a type of plaster with a finer grain. I had to mix up small batches because it dries very quickly. I applied globs of Hydrocal to the wall. I scribed horizontal lines in it while it was wet to create the strata lines. I randomly scraped and cut away portions on the different layers as it dried to shape the rocks. I repeated this process along the rock wall.

After it dried, I colored it. I mixed up a black wash. I added a drop of dish soap to wet the wash. This will allow the black wash to more easily flow into cracks and crevices. I randomly applied this to the wall. The color will fade as it dries.

After the black wash dried, I created a brown oxide colored wash without the dish soap. I applied this to the wall in the same manor. I will need to create a matching rock wall that will sit on the opposite side of the track at a later date. I will also add random rocks around the ridge.