Make Your Own Suiseki!- bonsaiTALK

Fig. 1 - An artificial stone created from
plaster can make an attractive accent
for your bonsai.

While suiseki traditionalists argue about whether it's correct to cut a natural stone, Martin Wolech has side-stepped the entire question by creating his own viewing stones using plaster-of-paris and foil.

You'll need the following:

Heavy gauge aluminum foil
about 5 lbs of Plaster-of-paris
Spatula or shaping tool.
Mold release or (Pam baking spray)
Duct tape
Mixing bowl and cup
Water-based paint or stain in dark earth tones
Feather or sponge, stippling brush
Varnish

Shape the foil into an attractive shape using a stone model or a shape from your own imagination.

Fig 2. - A basin stone shaped with
a depression to hold water
You might want to review the basic suiseki forms for guidance. Decide whether your stone will be stepped or peaked, a plateau stone or perhaps carry a basin or waterfall feature. If you find it difficult to create a mold, you can begin with a positive model formed in clay, or spread your foil across an actual piece of stone outcropping. TIP: Remember that the best suiseki are dark in color and are of a size that can be held in one hand.
At this point I wrap the mold with several layers of duct tape to help form a stable mold. Liberally spray the interior cavity with the mold release or "Pam" spray, otherwise you'll find it difficult to separate the mold after the plaster cures!
Next the plaster-of-paris is mixed according to the instructions. It will provide at least five minutes of working time, so you'll want to work quickly.
Spread the plaster into the mold using the spatula and let it set up overnight.

Fig. 3 - Coloring a plaster "stone"
After removing the last bits of plaster you can carve back into it with your carving tools to touch it up. If you'd like a smoother finish, go ahead and wet it down and rub it gently with a lint-free towel.
While it's still soft, Buff the bottom of your stone against a concrete sidwalk or paving stone to level it for display.
Once completely dry, you can stain and paint the model. This, after the initial shape, is the most challenging step in creating an artificial stone. I'd recommend that just before the paint dries, you should go back over it with a contrasting color and feather or sponge in veins to suggest impurities in the natural stone.
Once the stain is dry, proceed to glaze the "stone" with varnish or polyurethane sealant. You want a dull lustre, not a sheen, so be careful not to overdo this step.

Now that your "stone" is complete you can proceed to create a daiza (stand) for it. You can carve this from wood in the traditional way, or cast it from automotive body filler (BONDO) which I find to be a great time saver.

Fig. 4 - Completed "stone"