Making Garden Stones That Rock!

Pat "The Rock Lady" Aberg has been a rock lover all her life. Having grown up in Lake Michigan country, she has always had a collection of flat, skipping stones handy to send sailing across the water. So it isn't surprising that she found a way to incorporate them into her mosaic stepping stones.

Since Pat's mosaics so beautifully integrate nature with glasswork, we were surprised to learn that esthetics was not the motivating force that got Pat started adding pebbles and rocks. She was originally looking for a way to improve the traction on her glass stepping stones. She wanted to incorporate some sort of rough texture that a person's foot could grab hold of—as though anyone would actually step on these! The resulting designs have become so popular that Pat has picked up "The Rock Lady" nickname and people have come to recognize her signature touch.

Rayer's, Inc., makers of the popular DiamondCRETE mortar mix, recognized the unique attraction of Pat's designs and published sixteen of her patterns in a series called Pat Aberg's Rainbow's End Collection. One of her stones and a bench project were included in the recent Spectrum "Made with Mosaics" wall poster. Each pattern in the series incorporates some degree of rock and stone work and all include detailed instruction on the techniques Pat has developed.

So how's it done? It's a little trickier than you might guess, but still quite simple if you know the little construction secrets and follow Pat's advice.

Pat initially tried to incorporate pebbles and rocks in her designs without any special preparation, but ran into problems. The poured concrete tended to seep underneath the rocks, burying their faces and leaving her chipping and grinding away to expose them in the finished stone. As she tried to think of a way to prevent this, she hit upon the idea of using sand.

Pat's proven technique involves sprinkling an even 1/8-inch layer of sand in the areas of a mold where a pattern calls for pebbles or rocks. Sand should not be closer than 1/4-inch to any glasswork. The rocks and pebbles are then laid carefully into the bed of sand, keeping them in a single layer so that each one will become locked in the grip of the concrete to come. Where a larger rock is planned, add slightly more sand and mound it up a bit. Nestle the rock into the mound, brushing sand around the edges to fill any empty space. When all the glass and stones are in place, you're ready to pour the mortar mix.

Pat says that a common concern is the rocks shifting as the concrete is poured. Her advice: pour the concrete onto the glass pieces, not the sand and pebble areas. Pour slowly until it naturally flows over the rock areas. This will keep any shifting to a minimum. She also tells us that any clean sand will work for this process, although when she uses white DiamondCRETE (her favorite), Pat uses white sand because it won't leave any color residue behind.

When the stone has set and you turn it out of the mold, just brush the sand away from the rocks with a small brush-a paintbrush should do. You may need to use a razor knife to clean up a bit and create a smoother, finished look, but that's all there is to it.

Pat has used many different types of rocks successfully in her mosaic work. Aquarium gravel, aggregate, river rocks, agates and even flat sea shells are a few examples. If your supplier doesn't stock a selection, you can find polished stones at Wal-Mart, aggregate at garden centers and aquarium gravel at pet stores. Larger rocks work best when they are flat and smooth. River rock is ideal, so if you know of an unrestricted riverbed, you've got it made.

With this little bit of nature added, Pat's mosaic stone designs are a perfect fit in outdoor environs. Try Pat's published designs to get the hang of using rock and pebbles. Then try incorporating them (and other objects?) into designs of your own. Pat Aberg's Rainbow's End Collection should be available through your supplier. If not, contact the publisher, Rayer's, Inc (800- 228-4101) for help in finding a source near you.

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