Recovery of Cassiterite and Topaz Minerals from an Old Metallurgical Dump, Eastern Desert of Egypt

Abstract

Huge amounts of tailing dumps as a result of mines’ blasting operations were impacting both economical and environmental problems. This issue was in serious need to be treated with suitable solutions. Evaluation of one of these tailing dumps in the Eastern Desert of Egypt showed the presence of reasonable amount of cassiterite mineral reaching 0.199%. The mineral was found as finely disseminated particulates within varieties of quartz-feldspar-hornblende-biotite granitic formations. In the present study, the processing regime relied upon the synergy between reaching liberation size, and mineral over grinding due to its extreme brittleness. However, delicate grinding via attrition scrubbing was adopted to produce − 0.51 + 0.074 mm attrition product with fine fractions, reaching 62.31% and 37.59%, respectively. The recovery of cassiterite from the − 0.50 + 0.074 mm size fraction was accomplished by the physical difference between mother granitic formations that shielded the mineral grains. Under these conditions, joint shaking table/dry high intensity magnetic separation techniques were conducted to recover cassiterite mineral. The CCD statistical system was used as a mathematical approach to optimize the effect of the main working parameters of the magnetic separator, i.e., splitter inclination angle, and belt speed, and their interactions on the cassiterite recovery of the final concentrate. The suggested flow sheet succeeded to recover cassiterite mineral with a grade reaching 11.25% SnO2 with 94.08% operational recovery from a feed contained 0.19% SnO2. These results are highly imperative to achieve applicable processing flow-sheet of such kind of minerals’ secondary resources.

Genesis of the rare metals mineralisation in Um Safi acidic volcanics, Central Eastern Desert, Egypt

“…13 Th is predominant over U in the rhyolite of Um Safi, on contrary U is predominant over Th in the pyroclastics as well as in the younger granites, where kasolite is recorded as secondary uranium minerals as well as some U-bearing minerals such as plumbo-betafite, columbite, betafite and uranothorite. 14,15 The high radioactivity and mineralisation are controlled by syngenetic processes which is indicated by the existence of the recorded radioactive minerals, as well as post-volcanicity alterations which is indicated by ferrugination process and kaolinitisation process. 16…”