Although we are always astounded when we see a true piece of art painted in oil on canvas, sometimes we may wonder why oil painting is so expensive?
The answer is that oil paintings are made of oil mixed with color pigments - up to 75%. The higher the concentration of pigments is, the more expensive is the oil paint, and so the finished oil painting. But the reward is that the colors stay bright and brilliant over centuries.
What pigments for oil painting are made of
Over the centuries the pigments used for paintings changed. Among the first pigments that were used to paint where earth pigments. The colors that could be derived from these pigments include such colors as the sienna, the umber, green earth and a wide range of ochre. These pigments are very stable and don't chemically interact with oil so that the colors stay vibrant over centuries. That is why still paintings in caves are clearly visible even after thousands of years.
Later other natural and organic pigments have sources that are derived from vegetables or animals. Also, colored stones were ground to get all kinds of blue, green and red shades. But these were rare to find and therefore also very expensive.
Today almost all the pigments used are man-made chemicals. Therefore, oil paintings are much more affordable than they used to be centuries ago.
