MILLERITE
Millerite is an odd, scarce nickel sulfide mineral
(NiS). It tends to form radiating clusters or tufts of long, hairlike
needles. Some geodes in the Mississippian limestone outcrop belts of
America's Upper Mississippi Valley & Ohio Valley have millerite inside (see
below). Millerite crystals are very slender hexagonal needles with a
metallic luster and a brassy-gold color.
Millerite (above & below) - spray of millerite needles in chalcedony-lined
quartzose geode, from the Mississippian of Monroe County, Indiana, USA (CMC
public display, Cincinnati Museum Center, Cincinnati, Ohio, USA).
