A RARE EARTHS AND TRACE ELEMENT STUDY OF THE HONEYCOMB HILLS TOPAZ RHYOLITE IN JUAB COUNTY, UTAH

The Honeycomb Hills topaz rhyolite, a 4.7 Ma complex in west-central Utah, is quite unique. The Honeycomb Hills is characterized by two domes known as Bell Hill and Big Honeycomb Hill. The smaller of the two, Bell Hill, is characterized by vesicular rhyolite while the larger Big Honeycomb Hill exhibits many textural changes to include flow banding and welded tuffs composed of ash and breccia. Honeycomb weathering of the formation is extensive. In the past, it has been explored for beryllium, uranium, and Rare Earths and is currently being explored for Rare Earths, beryllium, lithium, and rubidium.

Students from the University of West Georgia have collected samples from both domes as well as a dry stream bed on the property. The samples have been cut and polished for analysis with a scanning electron microscope (SEM). Our research shows that there is a high elemental abundance of fluorine as well as notable amounts of Rare Earths such as ytrrium, cerium, and traces of lanthanum and neodymium. Other Rare Earths are also present in smaller quantities. In addition, ongoing research shows a notable amount of uranium present in some of the samples.

This research includes the production of thin sections for analysis with the SEM, identification of mineral phases, trace element analysis, and elemental mapping of areas of interest. Of particular interest is the presence of Rare Earths and their relative abundances. Thin sections of the rhyolite contain pyroclastics and individual minerals within the pyroclastic material. Samples collected from the dry stream bed are too weathered to produce thin sections.