I am working with Sculpey 3 polymer clay. I like this clay because it is easy to work with, is hearty when baked and takes finishes really well. I sculpt in black clay because my finishes really look nice over black.
Rocks and stones are porous so to get the clay to adhere well to the rock, I seal the rock with Golden Mediums GAC 100 Multi-Purpose Acrylic Polymer. I have used this product for many years for a wide variety of purposes and I like how it works in this case. It has a low sheen and it enhances the appearance of a rock or stone by bringing out it's natural color and texture. And it seals stones with one coat and dries quickly. Other acrylic products might work well for this too.
I use Pearl Ex Pigments for the finish on the tree. The gold bronze color works best if applied with your finger. Dip your finger into the powder, swirl your finger once with your thumb and lightly highlight the tree with the bronze on your finger. Use a brush, dabbing off the excess on a cloth, and apply the pigment where you cannot reach with your finger. This finish is intended to look old and antiqued.
I use live moss for the foliage of the tree. However, it may not be a great idea unless you plan on watering the moss at least a couple times a day or if you place the tree in an enclosed terrarium setting where it can maintain moisture all the time. Other options are to use dried moss or sculpt a likeness to foliage for the tree top. If you use live moss, inside or outside a terrarium setting, use only low drought moss like what you would find growing on a rock.
If you have any questions, please let me know.
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