Macrophotograph of Peacock ore (Chalcopyrite treated with acid) from Mexico; a copper ore Image #3047 3102 X 4747 pixels
Linear patterns in a thunderegg agate from Oregon. Thundereggs are nodule-like rocks and are found in layers of rhyolitic lava flows. Image # 3702
Macrophotograph of a polished slice of charoite; a rare silicate mineral found only in Siberia, Russia Image #2834 4689 X 3064 pixels