The minerals of the laboratory of Sòl-de-riu high schoolMaria Novella, Carolina Teleutsa, Laura Reverter, Nerea Sancho i Juanjo Savan

•Chemical composition: SiO2•Mohs hardness scale: 6,5-7•Habit: Amorphous•Luster: Pearly•Color: pattterned withbands, plumes, dendrites or inclusions bluish gray, gray, greenish gray,•whitish gray and reddish.•Row: White•Clearness: Translucent•Other information: Agate is not a specific mineral, but a set of microcrystalline varieties of quartz.

AGATHE

•Chemical composition: Fe3O4•Mohs hardness scale: 5,5-6•Habit: For the manufacture of refractory metals•Luster: Metallic•Color: Black iron•Row: Black•Clearness: Opaque•Other information: It’s crystallization is in cubic•It’s attracted by magnet•Sometimes works as a natural magnetic

MAGNETITE

OPAL

•Chemical composicion: SiO2·nH2O•Mohs hardness scale: 5.5–6•Habit: Irregular veins, in masses, in nodules•Luster: Subvitreous to waxy•Color: Colorless, white, yellow, red, orange, green, brown, black, blue•Row: White•Clearness: Opaque, translucent, transparent•Other information: Opal is a hydrated amorphous form of silica.

Chemical composition: KAl2(AlSi3O10)(OH)2 •Mohs hardness scale: 2-2.5•Habit: Massive to platy•Luster: Vitreous, silky, pearly•Color: Colorless, although light shades with yellow, brown, green or red•Row: White•Clearness: pearl, metallic, vitreous•Other information: Galena is the main ore of lead, used since ancient times. Because of its somewhat low melting point, it was easy to liberate by smelting.

MUSCOVITE (white mica)

HALITHE (Rock salt)•Chemical composition: NaCl.•Mohs hardness scale: 2.05-2.5.•Habit: Predominantly cubes and in massive sedimentary beds, but also granular, fibrous and compact.•Color: Colorless or white; also blue, purple, red, pink, yellow, orange, or gray.•Row: White.•Clearness: Transluced.•Other information: Salty flavor, fluorescent.

SILVITE (silvina)•Chemical composition: KCl.•Mohs hardness scale: 2.•Habit: As cubes and octahedral; columnar, in crusts, coarse granular, massive.•Luster: Vitreous to oily.•Color: Colorless to white, pale gray, pale blue ; may be yellowish red.•Row: White.•Clearness: Transparent.•Other information: It has a spicy flavor, salty to bitter taste.•

GALENA•Chemical Composition: PbS•Mohs hardness scale: 2.5-2.75•Habit: Cubes and octahedra•Luster: Metallic on cleavage planes •Color: Lead gray and silvery•Row: White•Clearnes: Transparent or translucent •Other information: It is the natural mineral form of lead sulfide.•This is the most important kind of lead, one of the most abundant sulfur minerals, there are a lot of varieties.

BIOTITE (or Black mica)•Chemical composition: K(Mg,Fe)3AlSi3O10(OH)2•Mohs hardness scale: 2.5–3.0•Habit: Massive to platy•Luster: Vitreous to pearly•Color: Dark brown, greenish-brown, blackish-brown, yellow, white•Row: Grey•Clearness: Transparent to translucent to opaque•Other information: Biotite is used extensively to constrain ages of rocks, by either potassium-argon dating or argon-argon dating.•It’s one of the minerals of granit

MALACHITE•Chemical composicion: Cu2CO3(OH)2 •Mohs hardness scale: 3.5–4.0•Habit: Massive, botryoidal, stalactitic, crystals are acicular to tabular prismatic•Luster: Ductile; vitreous in large cantidad•Color: Green•Row: Light green•Clearness: Opaque or translucent•Other information: Malachite was used as a mineral pigment in green paints from antiquity until about 1800.

PYRITE•Chemical composicion: FeS2 •Mohs hardness scale: 6-6,5•Habit: Cubic, faces may be striated, but also frequently octahedral and pyritohedron•Luster: Metallic, glistening•Color: Pale brass-yellow•Row: black-greenish-brown to black•Clearness: No•Other information: Pyrite remains in commercial use for the production of sulfur dioxide, for use in such applications as the paper industry, and in the manufacture of sulfuric acid.