Mineral Deposits, inventory

The known number of mineral deposits worked in Ireland runs to several hundred. It would be impractical to include every site in the inventory, especially as the inventory has to include aggregate and stone operations as well. Indeed, another Member State (Italy) has records of over 20,000 stone operations and over 3,000 metal mines. 

Refractory producers may have a unique or standard compliment of raw materials in their inventory to produce all of their alumina-silica brick products. Any one producer may have a special material that is unavailable to other producers. In North America, this was the case for Missouri diaspore until its depletion in the 1960s. As another example, one refractory producer had special bauxitic kaolin in Alabama used to produce 70% AI2O3 brick, and the deposit was subsequently depleted in the 1980s. In both cases cited, the producer with the special raw material had a competitive advantage during the life of its particular mineral deposit. 

Figure 6.5. Changes in soil organic C storage and mineral content along a chronosequence in Hawaii (Torn et al., 1997). The substrate for soil development are basaltic ash deposits of known age. Climate and vegetation are virtually the same across the sites. (A) Soil organic C inventory versus ash substrate age. The solid line is the whole mineral soil to the C horizon, and the dashed line is the top 20 cm. The increase and subsequent decrease in SOM with soil age is mostly due to changes in the subsurface mineral soil. (B) The correlation of soil carbon in mineral horizons with the amount of noncrystalline minerals.

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