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Front 1

Willemite

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Zn2SiO4
Color is usually colorless or white but can be tinted yellow, blue, red, brown and often green.
Luster is vitreous to resinous.
Transparency crystals are transparent to translucent.
Crystal System: trigonal; bar 3
Crystal Habits include typically short prismatic crystals although some prismatic crystals can be rather long with sometimes very steep rhombohedral terminations. Also as granular, lamellar and fibrous masses.
Cleavage in good in one direction (basal)
Fracture is conchoidal to uneven.
Hardness is 5.5
Specific Gravity is approximately 3.9 - 4.2 (above average for non-metallic minerals).
Streak is white.
Other Characteristics: strongly fluorescent green and sometimes phosphorescent.
Associated Minerals are zincite, franklinite, rhodonite, calcite, greenockite and other rare minerals.
Best field indicators are fluorescence, associations, luster, cleavage, and crystal habit.

Front 2

Olivine

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(Mg, Fe)2SiO4Color is a light near emerald green to the more common pale yellowish green; also found colorless, greenish brown to black. A near colorless specimen is likely nearly pure forsterite, while a greenish-brown to black specimen may approach pure fayalite in composition. Anything in-between is olivine.
Luster is vitreous.
Transparency: Crystals are transparent to translucent.
Crystal System is orthorhombic; 2/m 2/m 2/m.
Crystal Habits include flatten tabular to box shaped crystals, but good crystals are rare. More commonly found as grains in alluvial gravels and as granular xenoliths in magnesium rich volcanic rock. Also massive. Twinning is rare, but has produced star shaped trillings.
Cleavage is poor in two directions at 90 degrees, is more distinct in fayalite.
Best Field Indicators are color, hardness, mafic igneous or metamorphic environment of formation, lack of good cleavage and density.

Front 3

Garnet

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ALMANDINE Fe3Al2(SiO4)3 SG = 4.3 IR = 1.83 reddish brown to brown M-schists & gneisses; I-pegmatites (rarely)
ANDRADITE Ca3Fe2(SiO4)3 SG = 3.8 IR = 1.89 brown, black or green M-serpentinites & skarns; I-volcanic
GROSSULAR Ca3Al2(SiO4)3 SG = 3.5 IR = 1.75 colorless, orange or green M-contact marbles & serpentinites
PYROPE Mg3Al2(SiO4)3 SG = 3.6 IR = 1.73 dark red to ruby red M-serpentinites & gneisses; I-dunites & kimberlites
SPESSARTINE Mn3Al2(SiO4)3 SG = 4.2 IR = 1.80 orange, pink or brown M-gneisses & marbles; I-pegmatites & granites
UVAROVITE Ca3Cr2(SiO4)3 SG = 3.8 IR = 1.86 green M-serpentinites

Front 4

Zircon

Back 4

ZrSiO4
Color is brown, red, yellow, green, blue, black, and colorless.
Luster is adamantine.
Transparency crystals are transparent to translucent.
Crystal System tetragonal; 4/m 2/m 2/m
Crystal Habits: dipyramidal and prismatic as discussed above.
Cleavage indistinct in two directions, prismatic.
Fracture is uneven
Hardness is 7.5
Specific Gravity is 4.6-4.7
Streak white
Associated Minerals albite, biotite, garnets, xenotime and monazite.
Other Characteristics: is sometimes fluorescent and darker crystals may be radioactive due to impurities of rare earth elements. Also index of refraction is 1.92 - 2.01
Notable Occurances Seiland, Norway; Pakistan; Russia; Bancroft and Sudbury, Ontario, Canada and New Jersey and Colorado, USA.
Best Field Indicators are crystal habit, hardness, luster and density.

Front 5

Topaz

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Al 2 SiO 4 (F, OH) 3
Color is clear, yellow, orange, red, blue and green.
Luster is adamantine to vitreous.
Transparency crystals are transparent to translucent.
Crystal System is orthorhombic; 2/m 2/m 2/m
Crystal Habits include a prismatic crystal with usually two different prisms that produce a rounded or sharp diamond-shaped cross-section. The termination is typically capped by a dome forming a roof like top. Another dome can modify the termination producing a point at the juncture of the two domes. A basal pinacoid can flatten the prisms termination or truncate the top of the domes. The pinacoid, multiple domes and occasionally orthorhombic pyramid faces can produce a complex, multifaceted and well formed termination. Topaz can be granular and massive.
Cleavage is perfect in one direction, basal.
Fracture is conchoidal.
Hardness is 8.
Specific Gravity is approximately 3.4 - 3.5+ (above average)
Streak is white.
Associated Minerals include quartz, tourmalines, micas, brookite, cass

Front 6

Staurolite

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Fe2Al9Si4O22(OH)2
Color is reddish-brown, brown, and black.
Luster is vitreous to resinous to dull.
Transparency crystals are translucent to opaque.
Crystal System monoclinic; 2/m
Crystal Habits: the typical crystal are prismatic or tabular. Some crystals can have a psuedo-hexagonal cross-section but most are flattened into a more diamond shaped cross-section with two of the four points truncated. Twinning is seen in about 35% of the specimens encountered in nature. Twins are cross (+) or X-shaped and can be both at the same time. Crystals sometimes grown onto kyanite crystals.
Cleavage poor, in one direction.
Fracture is uneven to conchoidal
Hardness is 7-7.5
Specific Gravity is 3.7-3.8
Streak white
Associated Minerals include almandine, micas, kyanite and other metamorphic minerals.
Other Characteristics:
Notable Occurances Ducktown Tennessee, Georgia, Virginia and Montana, USA; Brazil; Scotland, Italy and France.
Best Field Indicators are color, associations, twinning and crystal h

Front 7

Kyanite

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Al2 SiO5
Color is blue usually but also can be white, gray or green. Color is often not consistent throughout the crystal and can be blotchy or in streaks.
Luster is vitreous to almost pearly.
Transparency crystals are transparent to translucent.
Crystal System is Triclinic; bar 1
Crystal Habits include flat, pinacoid dominated, prismatic crystals often embedded in metamorphic rocks and quartz veins.
Cleavage is good in one direction parallel to the flat pinacoid face.
Fracture is splintery.
Hardness is approximately 4.5 when scratched parallel to the long axis of the crystal and approximately 6.5 when scratched perpendicular to or across the long axis.
Specific Gravity is approximately 3.58+ (above average)
Streak is white.
Associated Minerals are biotite, staurolite, garnets, quartz, andalusite and sillimanite.
Other Characteristics: Sometimes intergrown with staurolite.
Best Field Indicators are crystal habit, color, luster and unusual hardness.

Front 8

Andalusite

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Al2 SiO5
Color is white, red, brown, orange and green.
Luster is vitreous.
Transparency crystals are transparent to translucent.
Crystal System is Orthorhombic; 2/m2/m2/m
Crystal Habits include prismatic crystals with a square cross section terminated by a pinacoid. also massive and granular.
Cleavage is good in two directions.
Fracture is splintery to subconchoidal.
Hardness is 7.5
Specific Gravity is approximately 3.15+ (above average)
Streak is white.
Associated Minerals are cordierite, biotite, feldspars, quartz, kyanite and sillimanite.
Other Characteristics: dark inclusions produce cruciform shapes in the variety chiastolite. Index of refraction is 1.632-1.638.
Notable Occurrences include Andalusia, Spain; Austria; California, USA and China.
Best Field Indicators are crystal habit, color, inclusions (if present) and hardness.

Front 9

Sillimanite

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Al2 SiO5
Color is white, brown and green.
Luster is silky when fibrous or vitreous otherwise.
Transparency crystals are transparent to translucent.
Crystal System is Orthorhombic; 2/m2/m2/m
Crystal Habits include rare prismatic crystals but mostly fibrous masses.
Cleavage is good in one direction lengthwise.
Fracture is splintery.
Hardness is 7.5 in large crystals but more fibrous forms are softer.
Specific Gravity is approximately 3.2+ (above average)
Streak is white.
Associated Minerals are garnets, biotite, feldspars, quartz, kyanite and andalusite.
Other Characteristics: fibers are brittle distinguishing them from asbestos minerals.
Notable Occurrences include Brazil, New England area and many European sites.
Best Field Indicators are crystal habit, color, brittleness and hardness if not fibrous.

Front 10

Titanite

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CaTiSiO5
Color is green, yellow, white, brown or black.
Luster is adamantine.
Transparency: Crystals are transparent to translucent.
Crystal System: Monoclinic; 2/m
Crystal Habits include elongated wedges that form tabular or platy crystals. Some crystals are not so elongated and can have a trigonal appearance similar to a flattened rhombohedron. Twinning is common and produces a twin that is shaped like a deflatted, caved-in football, only with flatter surfaces.
Cleavage is indistinct in two directions
Fracture is conchoidal
Hardness is 5 - 5.5
Specific Gravity is 3.3 - 3.6
Streak is white.
Associated Minerals are chlorite, anatase, calcite, quartz, zircon and feldspars.
Other Characteristics: Pleochroic if strongly colored.
Notable Occurances include Gilget, Pakistan; Mt Vesuvius, Italy; Kola Penn., Russia; Ontario, Canada and New York and California, USA.
Best Field Indicators are crystal habit, luster, hardness, twinning if present and color.

Front 11

Humite

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((Mg, Fe)2SiO4)3 - Mg(F, OH)2
Color is commonly yellow, but also white, brown or orange.
Luster is vitreous.
Transparency: Crystals are translucent.
Crystal System: Orthorhombic; 2/m 2/m 2/m
Crystal Habits include small prismatic to rounded crystals, but as is most commonly the case, as embedded grains.
Cleavage is poor in one direction, basal.
Fracture is subconchoidal.
Hardness is 6.
Specific Gravity is 3.2 - 3.3
Streak is white.
Associated Minerals include magnetite, diopside, spinel, biotite, serpentine, chondrodite, olivine and calcite.
Notable Occurrences are include Monte Somma, Mount Vesuvius, Italy; Paragas, Finland; Varmland, Sweden; Tilly Foster Mine, Brewster, New York, USA and some other localities.
Best Field Indicators are color, associations, environment of formation and hardness.

Front 12

Zoisite

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Ca2Al3(SiO4)3(OH)
Color is variable but well known as green, blue to violet and pink to reddish in color, Also grey, white or brown.
Luster is vitreous.
Transparency crystals are transparent to translucent.
Crystal System orthorhombic; 2/m 2/m 2/m
Crystal Habits include long, somewhat prismatic or tabular crystals with a typically dominant pinacoid that the crystal is often flattened against. The terminations are usually poorly developed. Also massive or granular.
Cleavage good in one direction lengthwise.
Fracture is uneven to conchoidal.
Hardness is 6 - 7
Specific Gravity is approximately 3.3
Streak is white.
Other Characteristics: striated crystals common, lengthwise. Also strongly pleochroic with an index of refraction of 1.68 - 1.72.
Associated Minerals include calcite, biotite, hornblende, quartz, corundum, andradite garnets and other metamorphic minerals.
Best Field Indicators only one direction of cleavage, associations, color, pleochroism and hardness.

Front 13

Vesuvianite

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Ca10(Mg, Fe)2Al4(SiO4)5(Si2O7)2(OH)4
Color is normally green, but also can be brown, yellow, blue and/or purple.
Luster is vitreous or greasy to resinous.
Transparency crystals are transparent to translucent.
Crystal System tetragonal; 4/m 2/m 2/m
Crystal Habits include prismatic crystals with an overall square cross-section. There is usually two sets of four sided prisms with one set being dominant.
The termination is usually a four sided pyramid that can be either steeply or gently sloped. The faces of the pyramids align with the faces of the prisms making an edge that is perpendicular to the length of the crystal (as opposed to the tetragonal mineral apophyllite). A pinacoid can truncate the pyramid or form the entire termination. Massive forms are common and difficult to distinguish from massive garnet.
Best Field Indicators crystal habit, color, cleavage and localities.

Front 14

Lawsonite

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CaAl2Si2O7(OH)2·H2O

Front 15

Melilite

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(Ca,Na)2(Al,Mg,Fe2+)[(Al,Si)SiO7]