Rhodochrosite is a manganese carbonate. Its value now resides almost entirely in the quality of its hot pink and deep red specimens, which are sought after by collectors and command extremely high prices.
Wulfenite is a mineral species composed of lead molybdate, Pb(MoO4), sometimes occurring in sufficient abundance to be mined as an ore of lead, but in practice its molybdenum content is greater. Even so, it is rarely used as an ore mineral because there are easier sources of lead or molybdenum available to exploit.
Stibnite is the principal ore of antimony. The mineral is widely admired for its spectacular crystalline habits, which exhibit extremes of sharpness, luster and size. Its principal metallic component, antimony, probably received its name from the Greek anthemon, describing its flowery appearance in clusters. The Latin name for the mineral, stibium, survives today as stibnite.
Gold is a bright yellow native element, long prized as an object of natural beauty. It has attracted the attention of human cultures for thousands of years, and its softness, resistance to corrosion and workability have made it a favored material for creating decorative jewelry and early coinage. Modern technological applications have displaced much of its historic use in jewelry and measuring wealth.
Sphalerite is common, but it does not often show up in casual collections of minerals, despite its occurrence in several different colors. This is perhaps because sphalerite is most commonly found in black or dark gray due to the frequent presence of iron impurities in its makeup.