Geode

Some of the most colorfully striking pieces are geodes, popularly labeled "Mexican coconuts." A Geode is a crystal-lined or agate-filled cavity which forms in the empty space left by a gas bubble in a lava flow, or lines a cavity in a rock fissure created by other processes. Geodes are characterized by a thin, dense layer of chalcedony (SiO2), surrounding a cavity of inward-projecting crystals. The interior crystals usually consist of quartz or calcite, and sometimes consist of barite, celestite, and various sulfides. Amethyst is the gem name given to purple quartz. Geodes may also be filled with rose quartz (pink), milk quartz (white), citrine quartz (yellow), and smoky quartz (black). Many of the beautiful geodes in the Jacklin Collection are from Mexico.

More on the saber-tooth cat can be found in the museum....