Abstract
The character of phosphorus-bearing minerals in the birmingham red iron ores and iron-bearing minerals in the eufaula bauxite deposits in Alabama were studied by petrographic, ore microscopic, luminescent microscopic, scanning microscopic, electron microprobe, and x-ray diffraction techniques. Fifteen types of phosphorus- bearing mineral grains were identified in birmingham iron ores by the characteristic sizes, shapes, and distributions. Size measurements and model and texture analyses permitted an estimate of potential liberation of phosphorus from the iron ores by beneficiation to be 27% in areas of previous mining and 60% in areas of current iron reserves. Fine grinding, selective flocculation, and flotation may constitute the best beneficiation techniques for future research. Hematite and geothite are the most important iron minerals in eufaula ferruginous bauxites, but pyrite, marcasite, and siderite are important iron minerals in some varieties, and lepidocrocite and ilmenite occur locally in minor quantities. Although simple screening will remove the coarsest iron-bearing grains, research on the utilization of high-gradient magnetic separation to reduce the amounts of iron-bearing grains is recommended.
