Crushed Rocks and Dimension Stone: Exploration, Evaluation and Exploitation in parts of Igarra Area, Southwestern Nigeria

Author(s): N. Egesi, J. I. Nwosu

The study area (Igarra) has been variously studied and is still receiving attention from workers on basement geology. Some investors in the quarry industry still make error in the selection of site for development and production of crushed rocks and dimension stone. The Octopol quarry in Igarra area was abandoned largely due to scanty information on the mineralogy of the schist quarried to ascertain the quality of the rock. However, granites, granite gneisses, charnockites and marbles present in the area can be suitable for dimension stone production. The marble should not be cleaned with wet cloth as the water will react with the rock to form a weak acid which attacks the polished surface and decolourize it to a dull and uninteresting surface. There is need to involve geoscientists in dimension stone site selection and production to ensure that proper rock is chosen, and also for quality control as mining progress rock quality varies.

Crushed rocks/Dimension Stone, Site Selection, Quarry Industry, Igarra Area, Southwest Nigeria

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