a solid, naturally-occuring obj w/a defined chemical composition. inorganic w/a crystalline structure, the building blocks of rocks
silicon plus oxygen or silicon dioxide (SiO2), Quartz and feldspar group silicates make up most
of Earth's continental crust
Many important mineral groups are not silicates.These include the carbonates, oxides, halides, sulfides, sulfates, and native metals.
The non-silicate groups are a source of many valuable ore minerals and building materials.
To be an ore, a mineral must occur in large enough quantities to be economically recoverable.
A rock is a naturally formed consolidated solid mixture
containing minerals, rock fragments, or volcanic glass
The terms igneous, sedimentary, and metamorphic refer
to how a rock was formed.
Made up of magma or lava
Made from sediments
Rocks changed by pressure or heat
Igneous: Formed from magma which cools and solidifies
below Earth's surface
Cooling and solidification take a long time resulting in large visible crystals
Coarse-grained like granite
Granite is mostly found in the continents
Formed from lava on or above Earth's surface
Cooling and solidification takes place relatively quickly resulting in very small crystals
Fine-grained like basalt
Basalt is in the ocean floor
classification of intrusive igneous rock
Rocks that are quartz-rich and contain
potassium feldspar and plagioclase feldspar
are called granite.
Rocks with no quartz and abundant
plagioclase feldspar and pyroxene are called
classification of extrusive igneous rock
These rocks may have the same compositions as intrusive
igneous rocks, but they always will have different textures.
Composition of the surrounding rock material will also
affect the extrusive magma.
A magma rich in silica (SiO2) forms rhyolite if it cools rapidly.
Similarly, gabbro's fine-grained volcanic counterpart is
basalt, which is a common rock in Earth's oceanic crust. If cooling starts off slowly below the surface with large
crystals, but then finishes at a faster rate to form small or
no crystals, the extrusive rock is called porphyry.
A texture in metamorphic rock which has lots of layers or bands
A texture in metamophic rock that has grains in more random orientations
a mineral has characteristics, a set of physical properties, but some of these properties can differ from sample to sample: cleavage, fracture, luster and streak, crystal shape, and hardness
The arrangement of atoms and the bonds between them can reflect the way a mineral breaks, how hard it is, and what types of crystal shape it has.
Minerals break along planes that cut across
relatively weak chemical bonds, a smooth, flat
surface is created.
Most minerals (except metals) have one or
more cleavage planes that also help in
determining their identity.
Some minerals do not split along well-defined
In such cases, a mineral will break unevenly.
resistance to scratching
use Mohs hardness scale- Friedrick Mohs 1812
whether a mineral can scratch another mineral
Luster and Streak
The way a mineral reflects light, whether it looks metalic or non-metalic...glassy or earthy(dull) or waxy
Sreak: color of min. in powdered form
Controlled by arrangement of atoms, look at types of symmetry
When clasts are loose on Earth's surface, they don't fit together perfectly. The empty space in between the grains