This is the Embossed Tile Technique that I found in 'Altered Surfaces' book by Chris Cozen (working artist for Golden products)....
I started with some mini canvases (2 x 3") that I found in a local art store. Apply Golden's Light Molding Paste evenly across the entire canvas with a palette knife. I then stamped an image using a foam stamp; I also added some wavy lines along the 2 sides of the canvas. I then let the paste dry overnight.
I experimented with wood mounted and unmounted stamps, but was not successful with them. Even using this foam stamp I sometimes found the image not sharp enough so I would respread the molding paste and stamp again. I was working on several canvases at one time and needed to clean the foam stamp after each canvas to ensure a sharp enough image.
After the molding paste had completely dried, I wet the entire surface with water using a brush. Don't soak it, but use enough water to allow the paint, you are about to apply, to flow. Using a brush and a small amount of paint, drop the paint in several places on the canvas. The colors should spread across the canvas. I used 2 colors: Golden's fluid acrylic ultramarine violet and phthalo green (blue shade). Do not cover the entire canvas.
I let the canvases sit overnight to make sure the first application of paints was dry. Then, again wet the surface of the canvas and apply an iridescent color to the areas that were left unpainted. I used Golden's fluid acrylic iridescent bronze. The paint must be dry before proceeding to the next step so I let them sit overnight again.
Using a palette knife, Golden Clear Tar Gel is applied over the entire canvas. The gel will appear milky when wet, but it does dry clear. The humidity was very high when I was working on this step of the project so I let the canvases sit for 2 days to dry thoroughly.