This is a detailed watercolor and ink illustration of a geode. The geode is a roughly triangular, irregular shape, with a light brown outer layer. The interior of the geode is exposed, revealing a complex network of white, cream, and light brown crystalline structures. These structures appear to be made up of concentric layers and intricate patterns, resembling a miniature landscape of hills and valleys. The geode rests on a base of darker, gray-toned rock with a textured, cracked surface. The illustration is rendered in a realistic style, with careful attention to detail and shading. The number '489' is visible in the upper right corner. Below the illustration, there is a handwritten inscription that reads 'Fig. 1. established by J.S. Mowley London.' The background is a warm, off-white color, providing a neutral backdrop for the geode.