Dereenalomane Barytes Mine was originally worked as a copper mine Traill and Thomas in 1840, producing 19 tons of copper, before shifting to barium sulphate, a heavy white mineral, ( used for paint, papermaking, etc . ) Josiah Wedgwood used it for making pottery.
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In 2002, mines produced 6, 634.5 kilograms of gold, 153, 834 kilograms of silver, five tons of lead, 267, 171 tons of copper, three tons of zinc, 18, 961 tons of iron, 7, 176 tons barium sulphate.
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Luminous reflectance measurements, Y, are required on both the sample material and a reference white; ISO 13803 details the use of a BaSO4 standard-Barium sulphate, a white crystalline solid having a white opaque appearance and high density as this material is a good substitute for a perfectly reflecting diffusor as defined under ISO 7724-2.
