Results of a complex estimation of the rocks in the phosphorite deposit of Toolse

The authors consider the problems of complex exploitation of the rocks in the phosphorite deposit of Toolse (Fig. 1), under the conditions of open mining. It has been stated that the carbonate rocks of the Middle Ordovician are suitable for producing building materials and cement. The glauconite sandstones and aleurolites of the Leetse Stage contain about 60 per cent of glauconite. The clays of the Varangu Member of the Ceratopygeous Stage, however, contain heightened amount of alkaline matter for which reason they cannot be used in the production of cement. The graptolytic argyllites of the Türisalu Member, of the same stage, seem to offer spropitious possibilities for complex mining, the main components in them being some rare and dispersed elements (molybdenum, vanadium, and others), whose content in the argyllites varies in dependence on the lithological character of the rock. principal scheme of complex processing of the argyllites has been devised (Fig. 3). The possibilities and the rational scope of complex working up of the carbonate rocks are discussed. The authors propose an economically grounded scheme of complex exploitation of the phosphorite deposit of Toolse (Fig. 2).