On Jarosite found in the Limonite Deposits of Mt. Kurikoma and the Omori Mine

Abstract

Jarosites are associated with limonite deposits in the environs of Mt. Kurikoma.
The limonite and jarosite ores grade laterally into each other within a single bed, i.e., from jarosite with thin layers of limonite, through alternating layers of limonite and jarosite, to limonite with thin layers of jarosite.
At places the jarosite contains diatom earth composed of several species.
Chemically, the ore is characterized by a higher content of Na₂O than the average (i. e., less than. 1.0% Na₂O) of other jarosites in Japan.
Jarosite-bearing limonite ore at the Omori Mine, occurs under a limonite bed which is characterized. by plant impressions. This ore is composed of goethite and fine particles of jarosite cemented by goethite. Fragments of plagioclase, quartz and rocks are enclosed in the ore.
The result of the spectroscopic analysis confirms the existence of Fe, Al, Na, and K in the ore. The X-ray powder diagram and differential thermal analysis curves show that this ore is a mixture of goethite and jarosite.