This classic specimen features a rich, 7.0 cm vug lined with large, drusy, dark gray metallic-bright pyrolusite crystals to 1.7 cm in a quartz matrix. Ex. Hans Karabecek Collection, a prominent Austrian mineral collector and industrialist, who lived from 1878-1963. He began collecting minerals at the age of 9, and developed a refined sense of taste such that only the very best specimens were selected. His collection went to Harvard after his death. Ex. Harvard Collection.