Works of "Research Collection"
Place Collected: Ducktown Dist.
Place Collected: Crystal River
Place Collected: Black Hills
Place Collected: St. Andreasberg
Place Collected: Badlands
Place Collected: S of Keystone, Black Hills
Place Collected: Garden of the Gods
Place Collected: Robert E. Lee Mine
Place Collected: Leadville District
Place Collected: Leadville District