Mooihoekite to chalcopyrite CuFeS, making it helpful in the study of ore deposits and the study of the central portion of the Cu-Fe-S phase system. Mooihoekite, chalcopyrite, talnakhite, and haycockite all play key roles in the study of ore genesis and beneficiation. Mooihoekite Mooihoekite is a copper iron sulfide mineral with chemical formula of CuFeS. The mineral was discovered in 1972 and received its name from its discovery area, the Mooihoek mine in Transvaal, South Africa. Mooihoekite crystallizes in the tetragonal crystal system. It has a short optical c-axis that is perpendicular to two longer a-axes of equal length. For Mooihoekite,
Ore Run Formation. The upper reaches of the stream flow over rock of the Burgoon Sandstone formation. Rock outcroppings are present in the watershed. The entire length of the stream flows over soil of the Deep-Wellsboro-Oquaga soil association, except for the headwaters, which are on soil of the Oquaga and another, minor soil association. Most of these soils are highly acidic. There is a bed of iron ore on Ore Run. The watershed of Ore Run has an area of . Ore Run is difficult to access. The Ore Run Falls are a cascade and slide waterfall on Ore Run. They are