On Rocks

This plaster rock is roughly 2" x 1". I wanted to capture some of the ground cover tones in the rock to create a cohesive look to the scenery.

I recently colored a few plaster rocks, and wanted to share the process. The initial rocks were made with a plastic rock mold (I believe Woodland Scenics sold it). Whenever I had some leftover plaster, I would fill the mold and leave the rocks for a future project. This being one of those projects, I don't remember exactly what plaster or ratio of water to plaster I used.

I completely finished the rocks prior to attaching any ground cover. This does two things. First, it provides a solid foundation for the rock to attach, and secondly, it allows the ground cover to completely cover the seams between the rock and the ground, adding to the look of a rock that is jutting out of the dirt.

This one is roughly 1" x .5"

The rocks are attached to the plaster/sculpt-a-mold scenery base with normal white glue, and left to dry.

After they are locked in place, I begin the coloring process. The colors below are what I used to achieve the coloring appropriate for rocks in my area. To me, what is more important than the exact coloring is the layers and variety of colors used. Rocks are rarely one solid, smooth, color. Varying the colors adds to the depth and texture of each rock. In the end, as with any element on a railroad or diorama, one rock may not be that impressive, but when viewed within the composition of the scene, they can add to the realism.

On that note, below are the colors and order used on these rocks -

Starting with a white plaster rock, I drybrush the following:

1. Craft Smart Acrylic - Suede
2. Craft Smart Acrylic - Tan
3. Model Master Acrylic - Railroad Tie Brown Flat
4. Model Master Acrylic - Grimy Black Flat

5. A wash of alcohol + India Ink, allowing the liquid to puddle in the various cracks

6. When this is dry, I lightly highlight the rocks with Liquitext Basics Acrylic - Titanium White

Those colors provide the base of each rock. They were then lightly reworked with the same colors as needed to get them to look how I wanted. Starting with the same base for each one provides a uniform look, suggesting they all came from the same mountain.

Products Used:
Craft Smart Acrylics
Model Master Acrylics
Liquitex Basics Acrylics
India Ink
Rubbing Alcohol (70% I think..?)