Pacific Ring of Fire Expedition. Photograph shows a piece of one of the chimney
spires in the next image. It has been cut in half and is 22 cm long.
The interior of the chimney is lined by a copper-rich mineral, chalcopyrite.
The gray and white zone near the exterior of the chimney is composed of
iron, zinc and barium-rich minerals called pyrite, sphalerite and barite.