Page 108 - Laboratory Manual in Physical Geology

MINERAL DATABASE (Alphabetical Listing)
Luster and Distinctive
Mineral Crystal Hardness Streak Properties Some Uses
System
ACTINOLITE Nonmetallic 5.5–6 White Color dark green or pale green; Green gem varieties are
(amphibole) (NM) Forms needles, prisms, and the gemstone “nephrite
asbestose fibers; Good cleavage jade”; asbestos products
Monoclinic at 56° and 124°; SG = 3.1
AMPHIBOLE: See HORNEBLENDE and ACTINOLITE

APATITE Nonmetallic 5 White Color pale or dark green, brown, blue, Used mostly to make
(NM) white, or purple; Sometimes colorless; fertilizer, pesticides;
Ca 5 F(PO 4 ) 3
calcium Transparent or opaque; Brittle; Transparent varieties
fluorophosphate Conchoidal fracture; Forms hexagonal sold as gemstones
Hexagonal prisms; SG = 3.1–3.4
ASBESTOS: fibrous varieties of AMPHIBOLE and SERPENTINE
AUGITE Nonmetallic 5.5–6 White to Color dark green to brown or black; Ore of lithium, used to
(pyroxene) (NM) pale gray Forms short, 8-sided prisms; Two make lithium batteries,
calcium good cleavages that intersect at 87° ovenware glazes, high
ferromagnesian and 93° (nearly right angles); temperature grease, and
silicate Monoclinic SG = 3.2–3.5 to treat depression

AZURITE Nonmetallic 3.5–4 Light blue Color a distinctive deep blue; Ore of copper used to
(NM) Forms crusts of small crystals, make pipes, electrical
Cu 3 (CO 3 ) 2 (OH) 2
copper carbonate opaque earthy masses, or short wire, coins, ammunition,
hydroxide and long prisms; Brittle; Effervesces bronze, brass; added to
Monoclinic in dilute HCI; SG = 3.7–3.8 vitamin pills for healthy
hair and skin; Gemstone
3–3.5 White
BARITE Colorless to white, with tints of Ore of barium, used to
Nonmetallic
BaSO 4 brown, yellow, blue, or red; Forms harden rubber, make
barium sulfate (NM) short tabular crystals and fluorescent lamp
rose-shaped masses (Barite roses); electrodes, and in fluids
Brittle; Cleavage good to excellent; used to drill oil/gas wells
Orthorhombic Very heavy, SG = 4.3–4.6
BAUXITE Nonmetallic 1–3 White Brown earthy rock with shades of Ore of aluminum used to
Mixture of (NM) gray, white, and yellow; Amorphous; make cans, foil, airplanes,
aluminum Often contains rounded pea-sized solar panels; Ore of
hydroxides No visible structures with laminations; gallium used to make LED
crystals SG = 2.0–3.0 bulbs and liquid crystal
displays in cell phones,
computers, flat screen
televisions
BIOTITE MICA Nonmetallic 2.5–3 Gray-brown Color black, green-black, or Used for fire-resistant
ferromagnesian (NM) to white brown-black; Cleavage excellent; tiles, rubber, paint
potassium, hydrous Monoclinic Forms very short prisms that
aluminum silicate split easily into very thin,
flexible sheets; SG = 2.7–3.1
K(Mg,Fe) 3 (Al,Si 3 O 10 )(OH,F) 2
BORNITE Metallic 3 Dark gray Color brownish bronze; Tarnishes bright Ore of copper, used to
(M) to black purple, blue, and/or red; May be weakly make pipes, electrical
Cu 5 FeS 4
copper-iron sulfide attracted to a magnet; H 3; Cleavage wire, coins, ammunition,
absent or poor; Forms dense brittle bronze, brass; added to
Isometric masses; Rarely forms crystals vitamin pills for healthy
hair and skin
CALCITE Nonmetallic 3 White Usually colorless, white, or yellow, but Used to make antacid
CaCO 3 (NM) may be green, brown, or pink; Opaque tablets, fertilizer, cement;
calcium carbonate or transparent; Excellent cleavage in 3 Ore of calcium
directions not at 90°; Forms prisms,
rhombohedrons, or scalenohedrons that
break into rhombohedrons; Effervesces
Hexagonal in dilute HCI; SG = 2.7
CHALCEDONY Nonmetallic 7 White* Colorless, white, yellow, light Used as an abrasive;
(NM) brown, or other pastel colors Used to make glass,
SiO 2
cryptocrystalline in laminations; Often translucent; gemstones (agate,
quartz No visible Conchoidal fracture; Luster waxy; chrysoprase)
crystals Cryptocrystalline; SG = 2.5–2.8
*Streak cannot be determined with a streak plate for minerals harder than 6.5. They scratch the streak plate.

FIGURE 3.21 Mineral Database. This is an alphabetical list of minerals and their properties and uses.

Mineral Properties, Identification, and Uses ■ 93