Rocks and Minerals (July 23)

Minerals

these are naturally occurring, inorganic, solid element, or compound with a definite composition, and a regular internal crystal structure.

Naturally occurring

Minerals are made by natural processes, these processes that occur in or on earth. Minerals form and exist in nature.

Inorganic

Minerals are not made by living organisms, not made up of living things or remains of living things.

Solid

It is not a liquid nor gas at a standard room temperature and pressure

Has a definite chemical composition

Minerals can be elements or compounds

Crystal

a solid in which atoms are arranged in regular, repeating pattern. They have an orderly arranged atoms.

Mineralogists

These people who study minerals. They classify minerals through their properties.

Luster

The property of minerals that indicates how much the surface of a mineral reflects light.

Mineraloids

substances that meet all criteria except crystallinity are called:

Hardness

A measure of its relative resistance to scratching.

Mohs Hardness Scale

The scale we used for hardness of a mineral

Friedrich Mohs

He created the mohs scale

Cleavage

where a mineral splits, subject to stress, along a specific plane as the result of a specific weakness in its crystal structure.

Fracture

The way a mineral breaks where not by the cleavage.

Streak

the color of the pulverized powder of a mineral or the colored mark it leaves when rubbed against a suitable surface

Color

This is usually expressed as the main body color of the mineral, along with the intensity of this colour.

Silicate Minerals and Nonsilicate Minerals

2 Mineral Groups:

Native elements, Carbonates, Oxides, Halides, Phosphates, Sulfides and Sulfates

Nonsilicate Minerals:

Silicates

Makes up 90% of Earth’s crust • Largest mineral group • Contains silicate atoms bonded to oxygen atoms • Often contain other elements like Ca, Fe, and Mg.

Nonsilicate

Constitute <10% of the Earth's crust • Do not contain the Si-O tetrahedron in their chemical structure.

Native Elements

Minerals that contain only atoms of one type of elements. • Make up a small number of minerals • Minerals in this group are rare and valuable.

Carbonates

Contain carbon atoms bonded to oxygen. • May include other elements such as Ca, Fe and Cu. • Found in areas where seas covered lands

Halides

Salts that can form when water evaporates. • Include minerals that contain elements F, Cl, Br, and I. • These elements combine with metal element.

Oxides

Contain one or two metal elements combined with oxygen. • Do not contain silicon.

Phosphates

Contain one atom of P, or Arsenic, bonded with oxygen. • Rare minerals

Sulfates

Contain S atoms bonded with O atoms.

Sulfides

Contain metal elements combined with S. • Do not contain oxygen.

Metallic Minerals

minerals which contain one or more metallic elements in their raw form. They are usually obtained from rare, naturally formed concentrations known as mineral deposits. • good conductors of heat and electricity

Nonmetallic Minerals

are composed of chemical elements that don’t have the properties of any metals. This means they are not good conductors of heat and electricity, they lack malleability and ductility, and they break down easily

Igneous, Sedimentary, and Metamorphic Rocks

Types of Rocks:

Ignis

Igneous came from a latin word:

Igneous Rocks

They are formed when magma or lava cools and crystallizes on or below the Earth’s surface.

Intrusive rocks and Extrusive rocks

two broad types of igneous rocks:

Intrusive (plutonic) Rocks

Igneous rocks solidify within Earth. - They are generally wholly crystalline and characterized by large crystal sizes visible to the naked eye because they cool slowly:

Extrusive (volcanic) rocks

igneous rocks are erupted onto the surface or into the atmosphere. - They have generally smaller crystal size and usually have a very-fine-grained or glassy groundmass that formed due to rapid cooling at the time of eruption.

Sedimentary Rock

They are formed by compaction of gravel, sand, silt or clay

Sedimentum

Sedimentary came from a latin word: (means settling)

Clastic, Biological, and Chemical

Three groups of sedimentary rocks:

Clastic

- made up of pieces (clasts) of pre-existing rocks loosened by weathering. These rocks have particles ranging in size.

Pebbles

Grains larger than 2mm are called:

Biological

- form when living organisms die, pile up, and are then compressed and cemented together.

Coal

(accumulated plant material that is carbon-rich)

Limestone

(rocks made of marine organisms).

Chemical

form by chemical precipitation that begins when water traveling through rock dissolves some of the minerals. These minerals are carried away from their source and eventually redeposited, or precipitated, when the water evaporates away.

Metamorphic Rock

Form when high temperatures and pressure act on a rock to alter its physical and chemical properties.

METAMORPHISM

– to change form

Foliated and Nonfoliated

2 groups of metamorphic rocks:

Foliated

- As pressure squeezes on a parent rock during recrystallization it causes the platy or elongated minerals within the rock to become aligned. they develop a platy or sheet-like structure that reflects the direction that pressure was applied in.

Nonfoliated

Do not have platy or elongated minerals and when these rocks undergo metamorphism the individual mineral grains do not align.

Rock Cycle

is a web of processes that outlines how each of the three major rock types—igneous, metamorphic, and sedimentary—form and break down based on the different applications of heat and pressure over time.