Search Mineralpedia – A Mineral Photo Database and Identification Guide
The buttercup flower is the namesake of this mineral after the Latin and scientific name for the flower ranunculus, in reference to the similarity of the color between the mineral and the flower. This rare mineral is found only at its type locality from the Kobokobo pegmatite in the Kivu province in the Democratic Republic of the Congo. Here it forms as a secondary mineral in oxidized uraniferous granite pegamatite. Ranunculite is highly radioactive.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/ranuculite.pdf
Named after the Rapid Creek type locality in Yukon Territory, Canada. At thetype locality, Rapidcreekite, a secondary mineral, is “formed along joint and bedding-plane surfaces of quartz-rich sideritic iron formation.” According to mindat.org, Rapidcreekite has other localities in Germany, Norway, and Romania.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/rapidcreekite.pdf