The mining and fabrication of structural and ornamental stones is a wide-spread industry involving the use of such rocks as granite, limestone, marble, sandstone, and
The general procedure is as follows. The sample is placed in the liquid of lowest specific gravity and is split into two fractions. The float
The Fluorspar Beneficiation Problem Acid grade fluorspar which is in great demand by the chemical and aluminum industries, must contain at least 97.5% CaF2 with
A process was developed in which iron-contaminated zinc was refined to readily acceptable purity. Aluminum added to the molten impure metal reacted with the iron,
This research has shown that & solid waste byproduct from secondary lead smelters can be successfully processed to recover copper and lead that is lost
A molten-salt electrorefining process was developed which provides a practical way for reclaiming vanadium from scrap generated in the processing of ductile vanadium into bar,
As in a pilot-plant-scale hammermill, the effect of moisture content in the pulverization of lignite in a similar size ball mill was observed to be
Coal normally contains trace amounts of fluorine ranging up to about 0.02 percent. These small quantities of fluorine generally are volatilized when coal is burned
During the past decade, several novel melting and casting techniques including vacuum arc melting, skull casting, Hopkins’ Process or electroslag melting, and electron-beam melting have
The copper in many large low-grade and small high-grade deposits cannot be economically recovered by conventional methods because the value of the copper content of