In 1995, a team of specialists composed of physicists, geologists, and paleontologists, carried out observations in the prehistoric caves of Pech-Merle. They took samples of pigments on the “Punctuated horses” panel. Besides horses and negative hands, there are several punctuation marks on this wall. They are black on the inside of the horses, and red on the outside. Analysis shows that the black lines are drawn with a mixture of manganese oxide and barium oxide. In some rare places, scientists also found charcoal.