GL5 Resources Essay 2005 Residual & Placer Q4 MS Describe and explain how each of the following types of mineral deposits may be naturally concentrated within the ‘surface processes’ part of the rock cycle: residual deposits placer deposits [25]
GL5 Resources Essay 2005 Residual & Placer Q4 MS Emphasis on surface processes-weathering, erosion, transport and deposition. Residual deposits Bauxite in Jamaica relate to mineral being dense, unreactive compared to host rock Host rock is limestone - dissolved away in solution by carbonation Placers need to be dense Unreactive lack cleavage hard (gold excepted) Beach placers, stream placers, bench placers Credit reference to examples eg Cornish Tin, South African Gold Total 25 marks