A. Abutment In coal mining, (1) the weight of the rocks above a narrow roadway is transferred to the solid coal along the sides, which act as abutments of the arch of strata spanning the roadway; and (2) the weight of the rocks over a longwall face is transferred to the front abutment, that is, the solid coal ahead of the face and the back abutment, .
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Iberia or modern Spain and Portugal, was one of if not the richest Roman province in the case of mineral ore from around the first century BC (Healy 1978). Containing deposits of the metals (Gold, Silver, Copper, Tin, Lead, Iron, and Mercury), it was very rich in Romans realised this, and there is evidence of largescale mining and .