How to Identify 10 Red and Pink Minerals

Alkali Feldspar

This very common mineral can be pink or sometimes a light brick-red, though usually, it is closer to buff or white. A rock-forming mineral with a pink or pinkish color is almost certainly feldspar.

Luster pearly to glassy; hardness 6.

Chalcedony

Chalcedony is the noncrystalline form of quartz that is found exclusively in sedimentary settings and as a secondary mineral in igneous rocks. Usually milky to clear, it takes on red and red-brown colors from iron impurities, and it forms the gemstones agate and carnelian.

Luster waxy; hardness 6.5 to 7.

Cinnabar

Cinnabar is a mercury sulfide that occurs exclusively in areas of high-temperature mineralization. If that's where you are, look for its lipstick-red color, once prized for cosmetic use. Its color also edges toward metallic and black, but it always has a bright red streak.

Luster waxy to submetallic; hardness 2.5.

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Cuprite

Cuprite is found as films and crusts in the lower weathered zone of copper ore deposits. When its crystals are well-formed, they are a deep red, but in films or mixtures, the color may range toward brown or purple.

Luster metallic to glassy; hardness 3.5 to 4.

Eudialyte

This oddball silicate mineral is quite uncommon in nature, being restricted to bodies of coarse-grained nepheline syenite. Its peculiar raspberry to brick red color makes it a staple in rock shops. It can also be brown.

Luster dull; hardness 5 to 6.

Garnet

The common garnets consist of six species: three green calcium garnets ("ugrandite") and three red aluminum garnets ("pyralspite"). Of the pyralspites, pyrope is yellowish red to ruby red, almandine is deep red to purplish, and spessartine is red-brown to yellow-brown. The ugrandites are usually green, but two of them — grossular and andradite — may be red. Almandine is by far the most common in rocks. All of the garnets have the same crystal shape, a round form with 12 or 24 sides.

Luster glassy; hardness 7 to 7.5.

Rhodochrosite

Also known as raspberry spar, rhodochrosite is a carbonate mineral that will bubble gently in hydrochloric acid. It typically occurs in veins associated with copper and lead ores, and rarely in pegmatites (where it may be gray or brown). Only rose quartz might be confused with it, but the color is stronger and warmer and the hardness, much lower.

Luster glassy to pearly; hardness 3.5 to 4.

Rhodonite

Rhodonite is far more common in rock shops than it is in the wild. You'll find this manganese pyroxenoid mineral only in metamorphic rocks that are rich in manganese. It's usually massive in habit, rather than crystalline, and has a slightly purplish-pink color.

Luster glassy; hardness 5.5 to 6.

Rose Quartz

Quartz is everywhere but its pink variety, rose quartz, is limited to pegmatites. The color ranges from the sheerest pink to a rosy pink and is often mottled. As with all quartz, its poor cleavage, typical hardness, and luster define it. Unlike most quartz, rose quartz does not form crystals except in a handful of places, making them pricey collectibles.

Luster glassy; hardness 7.

Rutile

Rutile's name means "dark red" in Latin, although in rocks it is often black. Its crystals may be thin, striated needles or thin plates, occurring in coarse-grained igneous and metamorphic rocks. Its streak is light brown.

Luster metallic to adamantine; hardness 6 to 6.5.

Other Red or Pink Minerals

Other truly red minerals (crocoite, greenockite, microlite, realgar/orpiment, vanadinite, zincite) are rare in nature, but common in well-stocked rock shops. Many minerals that are usually brown (andalusite, cassiterite, corundum, sphalerite, titanite) or green (apatite, serpentine) or other colors (alunite, dolomite, fluorite, scapolite, smithsonite, spinel) can also occur in red or pink shades.