There is an ancient Chinese saying: 'Consider the three planes in painting a rock¡¦. The ¡¥three planes¡¦ are the front view and the two sides. To the Chinese, rocks also have a spirit ¡V without spirit, rocks have no life.
Various brush strokes are used when painting rocks. Here are some general guidelines.
Start with the outline of the rock, using a dry brush and ink. Roll the brush gently with your fingers, making breaks in places according to the form of the rock. Unless you are painting a particularly smooth rock, the outline should generally look rugged. One side should be darker than the other, to make the distinction between light and shadow, back and front.
Paint the divisions in the rocks with a few strokes only, to show the general structure. Using slightly overlapping parallel lines, add a wrinkled effect in the shadows. Always shade from light to dark. Hold your brush at a slant, with the tip barely touching the paper at the beginning of each stroke. As it moves down the paper, the brush stroke broadens out.
To give more tonal variations to the rock, apply washes with a very light, diluted ink. Alternatively, apply a colour wash. Use red ochre for the lighter parts, and while it is still wet apply indigo to the shaded parts. Let these two colours blend naturally.
Either before or after the washes, dots can be added to indicate moss or lichen growing on the rock. Hold the brush upright and dip the tip into black ink, then let the brush make irregular and slightly overlapping groups of dots.
Once you have mastered rocks you can go on to paint mountains. But a mountain landscape is more than just a group of rocks. Your composition will need light and shade ¡V in other words, a degree of variation to create interest. The Chinese talk about appropriate groupings of mountains as having a ¡¥h'host-guest relationship'.