How do you carve stone? Stone carving has been around since before recorded time. We now carve more for enjoyment and decoration than out of necessity, and although the techniques may have improved, much stays the same. Here are the basic steps for carving stone or rock.

Step 1 The chicken or the egg-design vs. inspiration

Which comes first, the design idea or the stone that inspires you? The answer is, it depends on you! You can either discover a stone that suggests a design to you by the color or grain, or you can begin with a design idea, model it out of clay to work out the details, and then find a stone that will suit your idea.

Step 2 Choosing a stone

There are many different types of stone or rock available and suitable for carving. Let's begin with the softest, and work towards the hardest.

Soapstone, which is also known as steatite, has a composition of talc, and feels somewhat slippery like soap. It is so soft it can be carved with a knife. The ease of carving, coupled with the stone's ability to hold fine detail and take a polish, make it an ideal choice for your first carving.

Alabaster is also a soft stone, but has a tendency to flake or split along cracks in the stone that are not always apparent. A high-polished finish can bring out its beautiful colors and patterns. CAUTION: Wear a respirator when working with alabaster.

Limestone is another stone that is easy to carve and takes small detail work well. An advantage of limestone is that it is strong enough to support undercutting. Limestone has a very definite grain, and when carving, it breaks along the grain or "bed lines" easily. When carving across the grain, however, the stone is less reliable. Unlike many other rocks, limestone does not hold a polish. It's quite suitable for outdoor sculpture because it holds up well against acid rain.

Sandstone, like limestone, has a distinct grain that allows for easy flake removal. Carving sandstone is equivalent to using sandpaper on your tools, however, and it tends to dull them quickly. CAUTION: Wear a respirator when working with Sandstone due to the silica content.

Marble, although moderately hard to work, holds fine detail, comes in hundreds of colors, and gleams under a high polish. These qualities have made it the top choice of sculptors for millennia. Marble should only be used for indoor sculptures, however, since acid rain deteriorates the surface and erodes the stone in only a few years.

Granite is the hardest carving stone. Instead of actually carving with a hammer and chisel, you must use a carbide-tipped tools, diamond saws, and grinders. Granite can have a very fine grain or a very course one. It comes in a number of colors, can be highly polished and lasts outdoors. Many gravestones are carved from granite.

Step 3 Tools

Depending on the type of rock you will be carving, you will need some or all of the following tools: hammers (3 pound for removing large chunks, 2 pound for general carving, 1 pound for finer details), chisels (point for roughing out your carving, tooth for further refinement, flat and rondel for smoothing and to prepare the stone for finishing), pitching tool for removing large chunks of granite, tracing tool for more precision edges, rasps and rifflers smoothing, small grinder (such as a Dremel tool) for grinding, and sandpaper for shaping and polishing (course, medium, and fine grit). For granite, you will also need diamond saws and carbide-tipped pneumatic tools, and an air compressor. If you will be drilling your stone, you'll need a pneumatic rock drill and carbide-tipped bits.

You will need a work bench (also called a banker) that is very sturdy so you can pound on the heavy rock without collapsing the table.

Step 4 Safety

Safety glasses, respirator, earplugs, shock-resistant gloves, and a well-equipped first aid kit should be maintained and used for maximum safety.

Step 5 Sculpture Types

You will need to decide whether you want to do a relief sculpture wherein you carve an image that stands out from a flat surface, or a three-dimensional sculpture that can be viewed from all sides.

Step 6 Carving

Before you take hammer to chisel, determine the direction of the stone's grain. Stone tends to split along the grain, or bed lines, easily. Try to design your carving so the stone's grain runs along the length of the sculpture. Remember that any small detail that you carve will tend to break off if the grain is running crosswise. Sketch out your design on the stone (on the flat surface for a relief, or on all sides for a three-dimensional sculpture).

Rough out your carving with the pitching tool by hitting the top of the tool with a sharp blow of the hammer. Be sure to angle the tool towards the edge of the stone you want to remove. Use your chisels to cut parallel lines about an inch apart (don't go too deeply into the stone). Crosshatch the ridges you have made and then chisel along to pop off the cross-hatched ridges. Continue this process removing the stone you don't want to remain in the final sculpture. Work the entire carving to the same stage all around to keep the sculpture at the same stage. This will help you visualize the finished sculpture. Once you have the rough form, use the tooth chisel to further refine it, the rondel to make concave cuts, and the flat chisel to smooth the texture left behind by the tooth chisel.

Step 7 Finishing and Polishing

For softer stones, the rasps and rifflers shape and smooth the contours of the final sculpture. Use silicon carbide wet/dry sandpaper for polishing. Start with the courser grits (40-80), work to the medium grit (150-320), and finish with the finest grits (400-1500). This brings out the amazing patterns and colors of the stone.