Testing Stones for Carving, Part 3

We covered a basic visual test and then the hearing test. If your stone passed both those tests, it is ready for another visual test.

Wet the stone with water. The entire stone. Some people just squirt the stone a little, but this really just gives you an idea of the color of the stone, not the quality. So, this is not dab a little water on part of the stone and see how pretty it looks...

With the stone wet, look for any dark lines--typically thin and fairly straight.

I'm not talking about color variation like veins in marble. Look for lines that seem to go through or around the stone. This usually means there is a crack in the stone, or a layer of different material that will probably cause your beautiful stone to break into two or more pieces.

Tomorrow we'll talk about testing stones for softness!

Testing Stones for Carving, Part 2

Yesterday we covered the initial visual observation "test", today we will move on to a test involving a different sense--that of hearing!

Keep in mind that no test is 100%, that said, here goes.

This is the first test I was taught--I take my point and tap the stone lightly all over. Some people use a hammer, the theory is the same. Listen to the stone as you tap it. You are listening for a bright, clear sound. If you hear more of a "thud" or if it sounds kind of hollow, you don't want that stone. We call it "dead."

Try the tapping technique on several stones and listen to the differences.

This is good a time to mention that you should ALWAYS listen to your stones. Know what your stone sounds like when you start and listen to any changes that occur as you work it. You may be coming up on a hidden flaw that could destroy your piece if you ignore the sound change!

Your stones literally "talk" to you as you work. Part of your job as the sculptor is to listen.

Tomorrow we will talk about one more visual test for our stones.

Testing Stones for Carving, Part 1

If you pick up "any old stone" and try to carve it, you could be setting yourself up for more troubles and heartaches then if you take a little time and test the stone.

The first "test" is to visually inspect the stone on all sides for any imperfections. Imperfections include cracks and soft spots, veins of different materials (harder or softer than the main stone.) These flaws can lead to the stone breaking or perhaps challenging the sculptor due to the differences in tools and techniques required.

Look at all sides of the stone for obvious imperfections. Because stones are natural, there will be (naturally) imperfections. Some will be hidden inside and you won't know they are there. Others will be glaring.

Some imperfections add "personality" or "character" and you may be tempted to work around them. These imperfections include imbedded crystals and fossils, and stones with big holes or pockets in them. While these may be beautiful to look at and could possibly be worked into an awesome piece by an advanced carver, they indicate that the stone has different levels of hardness which makes carver more of a challenge.

For a beginner, it is recommended that you have as few imperfections as possible. A stone that is consistent throughout in grain and character will be much easier for you to carve.

Tomorrow in Testing Stones for Carving, Part 2 I'll teach you the first test I ever learned!