Home > Uranium Minerals II – November 29 > MS0818 Natrozippeite, Uranopilite

Natrozippeite, Uranopilite - Sold


The Happy Jack mine was an important producer of uranium during America's uranium boom days (1950s-1960s) (San Juan Record, 2009). As seasonal rain waters percolated through the mine, they would slowly deposit colorful uranium minerals on the mine walls. This specimen features an intergrowth of two uranium minerals, orange natrozippeite and yellow uranopilite. This is a fragile mineral specimen that may suffer some loss (shedding) in shipment.

Zippeite is a uranium sulfate mineral originally named after Austrian mineralogist František Xaver Maximillian Zippe (1791–1863), Austrian mineralogist and geologist. In a study of zippeite specimens, Frondel et al. (1976) noted variable cation contents for zippeite and named several separate species, including sodium zippeite. A later change by the International Mineralogical Association (Burke, 2008) sets the currently accepted as natrozippeite. The mineral forms orange masses, here admixed with yellow uranopilite. Uranopilite is a hydrated uranium mineral, named for its uranium content and felt-like texture Frondel (1958) (note: file size 24.6MB). A crystal structure solution by Burns (2001) established the ideal formula of uranopilite as (UO2)6SO4O2(OH)6·14H2O.

This specimen was part of the personal collection of Ralph Merrill, proprietor of the prolific mail order business Minerals Unlimited. Merrill's collection card and label ship also with the specimen. Although not stated on the collection card, Ralph Merrill almost certainly obtained this specimen from Salt Lake City collector Otto Ray in the early 1960s.