Chapter 3 Flashcards
mineral
naturally occurring homogeneous solid solid formed by geologic processes with an ordered internal arrangement of atoms, ions, or molecules, and a composition definable by a chemical formula. Some believe it must be inorganic (not produced by an animal or plant)
Naturally occuring
a mineral forms by natural Earth processes (not human made)
Homogeneous
a piece of a mineral contains the same pure mineral throughout
Formed by geologic processes
traditionally implied processes such as solidification or precipitation which do not involve living organisms.
Solid
minerals maintain their shape indefinitely under normal conditions. Therefore, liquids like oil and water and gases like air and propane cannot be minerals
ordered internal arrangement of atoms
important characteristic that separates minerals from substances that may fit all other parts of the definition.
crystalline structue
atoms in minerals occupy this position in a grid
glasses
solids in which atoms occur in random clusters than in a crystalline structure
Definable chemical composition
elements present in a mineral and the proportions of their atoms can be expressed by a simple formula
Crystal
when a mineral grows without interference from other minerals, it develops smooth flat surfaces and a symmetrical geometric shape
grain
irregular or fragmented piece of mineral
specimen
single piece of mineral either crystal or grain
rock
coherent, naturally occurring, inorganic solid consisting of an aggregate of mineral grains, pieces of older rocks, or a mass of natural glass.
physical properties
how it looks (color and luster), breaks, feels, smells, and even tastes
diagnostic properties
they help immediately identify an unknown mineral or rule it out as a possibility
ambiguous properties
may vary in different specimens of the same mineral.
ex: color is a notoriously ambiguous property in many minerals; size doesn’t really matter either
Luster
the way light interacts with its surface
Diagnostic property
metallic luster
shiny and opaque like an untarnished piece of metal
nonmetallic luster
look earthy (dull and powdery like dirt), glassy, waxy, silky, or pearly
Color
different wavelengths absorbed or reflected by the minerals atoms
diagnostic property for metallic minerals
Streak
color of its powder
determine by rubbing mineral against an unglazed porcelain plate
Hardness
measure of how easily it can scratch or be scratched by other surfaces
Mohs hardness scale
relative scale
a mineral can scratch those lower in the scale but cannot scratch those that are higher
Crystal habit
preferred crystal shape that forms when it grows unimpeded by other grains
Crystal growth requires very specific conditions
breakage
the way a mineral breaks is controlled by the zones of weak bonds in its structure
Fracture
occurs when there are no zones of particularly weak bonding within a mineral
Cleavage
occurs when bonds holding atoms together are weaker in some directions that others
Specific gravity
SpG
comparison of its density with the density of water
Magnetism
diagnostic property because so few minerals are magnetic
Feel
greasy r slippery because their chemical bonds are so weak
Taste
chemical property
Odor
some minerals and their streaks have specific odors
Reaction with Dilute Hydrochloric Acid
Many minerals that contain carbonate anion fizz when the come in contact with that acidq
Tenacity
the way materials respond to being pushed, pulled, bent, or sheared. (malleable, brittle, ductile, flexible, elastic)
Ore minerals
containing metals that can be separated from the rest of the elements in the mineral usually by melting
