caption: The image shows a painting of three different types of rocks on a white paper, which is part of the collection of the British Museum of Natural History. The rocks are arranged in a triangular formation, with the largest rock in the center and two smaller rocks on either side. The colors of the rocks range from light brown to dark brown, and the texture of the stones is rough and bumpy. The painting has a vintage feel to it, with a muted color palette of blues, greens, and yellows.