Physical Geology 1330 – Lecture 5 Minerals and Matter – Mineral Groups

Flashcards covering major mineral groups, the most abundant elements in Earth's crust, various silicate structures, and key rock-forming minerals, differentiated by mafic and felsic characteristics, based on Physical Geology 1330 lecture notes.

Oxygen (O)

The most abundant element in Earth's crust (47% by weight), and the only anion listed among the most abundant.

Silicon (Si)

The second most abundant element in Earth's crust (28% by weight), which forms covalent bonds with aluminum.

Aluminum (Al)

The third most abundant element in Earth's crust (8% by weight), which forms covalent bonds with silicon.

Silicates

A major mineral group characterized by the (SiO4)-4 anionic complex (silica tetrahedron); they constitute approximately 92% of Earth's crust due to the abundance of Si and O.

Carbonates

A major nonsilicate mineral group characterized by the (CO3)-2 anionic complex, exemplified by calcite, limestone, and dolomite.

Halides

A major nonsilicate mineral group characterized by halogen anions like (Cl)-2 or F-1, exemplified by halite (salt) and fluorite.

Oxides

A major nonsilicate mineral group characterized by the O-2 anion, exemplified by magnetite and hematite, and are often economically important.

Sulfides

A major nonsilicate mineral group characterized by the S-2 anion, exemplified by pyrite and galena.

Sulfates

A major nonsilicate mineral group characterized by the (SO4)-2 anionic complex, exemplified by gypsum (main component of drywall).

Native Elements

A major mineral group consisting of minerals composed of a single element, such as copper or gold.

Phosphates

A major nonsilicate mineral group characterized by the (PO4)-3 anionic complex, exemplified by apatite (found in teeth and bones).

Silica Tetrahedron

The fundamental building block of silicates (SiO4)-4, composed of four oxygen atoms surrounding a central silicon atom, held by strong covalent bonds.

Isolated Tetrahedron Silicates

A silicate structure where individual silica tetrahedra are bonded together by intervening cations (ionic bonds), as seen in minerals like olivine.

Single Chain Silicates

A silicate structure formed by a continuous chain of covalently bonded silica tetrahedra, with cations linking the chains, as seen in pyroxene.

Double Chain Silicates

A silicate structure formed by two parallel single chains of silica tetrahedra covalently bonded together, as seen in amphiboles like hornblende.

Sheet Silicates

A silicate structure where silica tetrahedra are connected continuously from end to end, forming flat sheets, as seen in biotite and muscovite.

Framework Silicates

A silicate structure forming a 3-D network where all silica tetrahedra are interconnected, as seen in quartz and feldspar.

Cleavage

The tendency of a mineral to break along specific planes of weakness, often characteristic of its internal atomic structure (e.g., silicate structure).

Mafic Minerals

Dark-colored silicate minerals rich in iron (Fe) and magnesium (Mg), including olivine, pyroxene, amphibole, and biotite.

Felsic Minerals

Light-colored silicate minerals, typically rich in framework silicates like feldspar and quartz, including muscovite, plagioclase, orthoclase, and quartz.

Olivine

A mafic silicate mineral with the formula (Mg,Fe)SiO4, characterized by an isolated tetrahedron silicate structure.

Pyroxene

A mafic silicate mineral with the formula (Mg,Fe)SiO3, characterized by two cleavage planes and a single chain silicate structure.

Amphibole

A mafic silicate mineral with the formula Ca2(Fe,Mg)5Si8O22(OH)2, characterized by two cleavage planes and a double chain silicate structure (e.g., hornblende).

Biotite

A mafic sheet silicate mineral with the formula K(Fe,Mg)3AlSi3O10(OH)2.

Muscovite

A felsic sheet silicate mineral with the formula KAl2(AlSi3O10)OH)2.

Plagioclase

A felsic framework silicate mineral from the feldspar group with the formula (Ca, Na)AlSi3O8.

Orthoclase

A felsic framework silicate mineral from the feldspar group with the formula KAlSi3O8.

Quartz

A felsic framework silicate mineral with the formula SiO2, known for its 3-D network of silica tetrahedra.