A. Will leave mark on paper Argentite Shiny, blackish Lead-gray color 2-2½ to lead gray that tarnishes to dull black; knife cuts it smoothly; heavy; may occur as masses and coatings Galena Grayish black Shiny lead-gray 2½ color; heavy; cube-shaped fragments and crystals Graphite Black Steel-gray color; 1-2 greasy feel; very soft; splits into thin flakes B. Does not readily leave mark on paper but can be scratched by ordinary pocket knife Chalcocite Grayish black Shiny lead-gray 2½-3 color that tarnishes to dull black; knife cuts it smoothly; may have black sooty coating; commonly occurs as compact or granular masses Hollandite Black Silvery-gray 4-6 color; may occur as rounded masses C. Cannot be scratched by ordinary pocket knife Braunite Steel gray or Dark steel-gray 6-6½ black color and submetallic luster Hematite Dark reddish brown Steel-gray color; 5½-6½ commonly occurs (may be as granular or softer) compact masses; shiny, scaly variety is _specular_ hematite; notice streak