A Study of the Concentration of a Low-Grade Manganese Ore from the Ennis District

The purpose of the investigation was to determine the most effective means of concentrating the manganese in the ore. The study was that of identification of the minerals present. This showed the presence of oxides of manganese and iron, and carbonates of calcium and manganese. Methods of investigation were planned to determined whether the ore could be concentrated effectively by gravity concentration methods. ­

Helena and Ennis Talc Deposits

The purpose of this report is to collect geologic data concerning two Montana talc occurrences at Helena and Ennis and to offer some explanation as to their origin. The two deposits cited are in somewhat similar lithologic settings and both possess the same mineralogical and structural features. Because of this similarity only the Helena deposit is covered in detail.

Geology of a Kyanite Deposit Near Ennis, Montana

A deposit of kyanite, an aluminum silicate mineral used in the ceramic industry, occurs in the low foothills of the Gravelly range about 10 miles south of Ennis, Montana. This study deals primarily with the character and origin of the deposit, and its relationship to the surrounding rocks.