Ferruginous limestone

Kalk-echtlieit. /. fastness to lime, -einlagerung, /. calcareous deposit, -eisengranat, m. lime-iron garnet, andradite. -eisenstein, m, ferruginous limestone, kalkempfindlich, a. sensitive to lime. Kalkempfindlichkeit, /. sensitiveness to lime, kalken, kalken, v.t. lime. 

Ferruginous limestone contains sufficient iron oxide to colour the deposit yellow or red. 

In this case study, the selected phases are pyrite, amorphous FeS, calcite (present in limestones in the roof strata Fig. 5), dolomite (possibly also present in the limestones), siderite (which occurs as nodules in roof-strata mudstones), ankerite (present on coal cleats in the Shilbottle Seam), melanterite and potassium-jarosite (representing the hydroxysulphate minerals see Table 3), amorphous ferric hydroxide (i.e., the ochre commonly observed in these workings, forming by precipitation from ferruginous mine waters), and gypsum (a mineral known to precipitate subaqueously from mine waters with SO4 contents in excess of about 2500 mg/L at ambient groundwater temperatures in this region, and with which most of the mine waters in the district are known to be in equilibrium). In addition, sorption reactions were included in some of the simulations, to contribute to the mole transfer balances for Ca, Na, and Fe. 

White Cement. Portland cement made from non-ferruginous raw materials, i.e. chalk (or low-iron limestone) and china clay. The Fe203 content is <1%. 

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