The Linwood Mine, located in Scott County, Iowa, contains a variety of interesting mineralization. This project focuses on the barite found at the locality, and attempts to explain the variety of crystal forms and habits, monocrystalline and multicrystalline barite, as well as the distribution of these forms in relation to environment of formation. Observations of the barite, as well as the host rock, use of x-ray powder diffraction, UV fluorescence studies, and cathodoluminescence studies were all used to compare barites. X-ray powder diffraction analysis of the barite samples showed no significant difference in the lattice parameters of monocrystalline and multicrystalline barites. Studies of cathodoluminescence in barites showed that there is no correlation between the fluorescence of barite and CL coloration. These new data were combined with previous studies of the barite and the cavities where it was found. All these attributes were entered into ArcView GIS to create a database, which allowed for the spatial analysis and the comparison of many different characteristics. Use of the spatial analysis supplied information that suggests two different environments of formation, phreatic for the monocrystalline and vadose for the multicrystalline barites. Observations of the barite found in the Linwood Mine locality also suggest that these barites were formed in a different event than that of the barites found in the Mississippi Valley Zinc-Lead district.
Jill Leonard, ’03 Blue Grass, IA
Majors: Geology, Environmental Studies
Sponsor: Paul Garvin