geode
A geode is a hollow mineral formation found in certain rocks. Typically, a geode is almost filled by inward-growing crystal spikes, usually of quartz. Geodes range between 20 millimeters and 1 meter across.
A geode is a hollow mineral formation found in certain rocks. Typically, a geode is almost filled by inward-growing crystal spikes, usually of quartz. Geodes range between 20 millimeters and 1 meter across.
