Introductory Geology: Minerals and Mineral Properties Flashcards

Vocabulary flashcards focusing on fundamental mineralogy concepts, physical properties, bonding mechanisms, and identification characteristics from geology lecture notes.

Rock

An Earth material made from minerals, typically composed of multiple mineral species, though some types are monomineralic.

Monomineralic Rock

A rock composed of only one single kind of mineral, such as limestone (calcite), rock salt (halite), or glacial ice.

Mineralogy

The study of minerals.

Mineralogist

A scientist who studies minerals, including their composition, uses, and properties.

Mineral

A homogeneous, naturally-occurring, solid, and generally inorganic substance with a definable chemical composition and an orderly internal arrangement of atoms.

Homogeneous (Mineral Context)

A characteristic of a substance indicating it is the same through and through and cannot be broken into simpler components.

Synthetic Minerals

Man-made mineral equivalents produced through artificial processes, such as industrial diamonds, rather than natural geological processes.

Crystal Lattice

The organized, repeating three-dimensional atomic structure of a mineral crystal solid.

Organic Substance

A substance composed of carbon bonded to hydrogen with varying amounts of oxygen, nitrogen, and other elements. Carbon alone is not considered organic.

Polymorphs

Two minerals that share the exact same chemical composition but possess different crystal structures, such as diamond ($C$) and graphite ($C$).

Physical Properties

Visual and chemical properties of minerals—such as color, streak, luster, hardness, specific gravity, crystal habit, and cleavage—used by geologists for identification.

Streak

The color of the pulverized powder of a mineral, obtained by scraping the mineral across an unglazed porcelain plate.

Luster

The appearance of a mineral's surface in reflected light or the manner in which it scatters light.

Hardness

A measure of a mineral's resistance to scratching, which represents the strength of the atomic bonds in its crystal lattice.

Mohs Hardness Scale

A qualitative relative hardness scale ranging from talc ($1$) to diamond ($10$), with reference materials such as a fingernail ($2.5$), glass ($5.5$), and a streak plate ($6.5$).

Specific Gravity

The ratio of the weight of a substance to the weight of an equal volume of water, which is equivalent to density.

Crystal Habit

The characteristic, consistent external shape or growth pattern exhibited by an individual crystal or aggregate of crystals.

Cleavage

The tendency of a mineral to break along designated planes of structural weakness in its crystal lattice, producing flat, shiny surfaces.

Fracture

The breaking of a mineral in an irregular, non-planar manner due to equal atomic bond strength in all directions.

Conchoidal Fracture

A type of fracture where a mineral breaks along smooth, scoop-shaped curved surfaces unrelated to weakness in the crystal structure, common in obsidian and quartz ($SiO_2$).

Tenacity

A mineral's structural resistance to breaking, crushing, bending, or deforming under applied stress.

Brittle Minerals

Minerals held together by bonds such as ionic bonds that shatter into small pieces when struck.

Malleable Minerals

Minerals with metallic bonds that allow them to be hammered easily into different shapes without shattering.

Sectile Minerals

Minerals, such as gypsum and talc, that possess the tenacity allowing them to be sliced into thin shavings.

Elastic Minerals

Minerals, such as the micas, that bend under stress and return to their original shape when the force is released.

Opaque

An optical clarity classification describing a mineral through which no light is transmitted.

Translucent

An optical clarity classification describing a mineral through which light passes, but no distinct image can be seen.

Transparent

An optical clarity classification describing a mineral through which both light and a clear image are visible.

Double Refraction

An optical property demonstrated by transparent calcite where light passing through splits, causing a double image to appear.

Effervescence

The chemical reaction property where carbonate minerals, such as calcite ($CaCO_3$), fizz and release carbon dioxide gas ($CO_2$) when exposed to dilute hydrochloric acid.