For centuries mankind has utilized naturally occurring iron oxides as coloring agents. It is only in the last century that people have developed ways to chemically synthesize these natural reactions. More recently the Hoover Color Division of CATHAY INDUSTRIES has worked in conjunction with iron oxide recovery to modify a naturally occurring process to produce a series of unique iron oxides pigments. Not only is the EnvironOxide® range a good source of color, it is also a by-product of a successful reclamation project.
Most people recognize that sulfur is a major contaminant in coal. As coal is burned, sulfur is released into the atmosphere where it combines with moisture to produce acid rain. Coal with even higher sulfur levels is unsaleable and left at the mines in overburden piles. What most people fail to recognize is that the sulfur in coal is not elemental sulfur, but an iron sulfide that is more commonly referred to as the mineral Fool’s Gold. When Fool’s Gold comes into contact with water it dissolves, becoming sulfuric acid. A serious environmental condition is created when this acid migrates into streams and rivers, killing off both plants and animals.