they’re everywhere!. what is a mineral? a mineral: is naturally-occurring. ○ not manmade is an...
TRANSCRIPT
MINERALS!
They’re everywhere!
What is a mineral? A mineral:
is naturally-occurring. ○ not manmade
is an inorganic solid.○ It has never been a part of a living thing.
has a definite chemical composition.○ It has specific elements that make up its compounds.○ NaCl is always halite, which is table salt. It is a
compound of sodium and chlorine.has an orderly arrangement of atoms.
○ Minerals are made of crystals, which have specific shapes.
○ All minerals are solids.
Atom Patterns in Minerals Minerals are crystalline solids.
The atoms of minerals are arranged in patterns that repeat.
A crystal is a solid in which the atoms are arranged in orderly, repeating patterns.
A crystal system is a group of crystals that hasa similar atomic arrangement.a similar overall crystal shape.
http://www.minerals.net/MineralMain.aspx
The Structure of Minerals
Crystal Systems of Minerals Hexagonal Six-sided crystals Examples:
EmeraldsAquamarine
Crystal Systems of Minerals Tetragonal Example:
ZirconCassiterite from Madagascar
Apophyllite
Crystal Systems of Minerals Cubic Examples:
Halite, which is common table salt.
Fluorite, which is an additive in toothpaste used to prevent cavities.
Crystal Systems of Minerals Orthorhombic Example:
SulfurTopaz
Crystal Systems of Minerals Monoclinic Example:
Selenite gypsum
Crystal Systems of Minerals Triclinic Very little
symmetry Example:
amethyst
More on crystals . . . There are about 4000
different types of minerals on Earth.
Crystals that develop in a tight space will have small, barely visible crystal shapes.
Crystals that develop in open spaces will have more room to grow larger, visible crystal shapes.
Crystals from Magma
Hot, melted rock material that is under Earth’s crust is called magma.
Magma is loaded with compounds that can form minerals.
If magma cools slowly, the crystals have more time to form and can grow quite large.
If magma cools quickly, smaller crystals form and individual crystals can’t be seen.
Crystals from Solution Crystals can form when minerals dissolve in
water and the water evaporates. http://news.nationalgeographic.com/news/2007/04/photogalleries/gi
ant-crystals-cave/
Death Valley Salt fields were formed from halite that came out of solution as water evaporated.
Devil’s Golf Course, Death Valley, California
Mineral Compositions & Groups Ninety-two elements occur naturally in Earth’s
crust.
Most of Earth’s crust is composed of only 8 of these elements.
Silicates are minerals that contain a compound of silicon and oxygen bonded together, usually with another element.Silicon and oxygen are the two most abundant
elements in Earth’s crust.
