Minerals are all around us Mighty Minerals Minerals are all around us

Fascinating Fact The elements oxygen, silicon, aluminum, iron, magnesium, calcium, potassium, and sodium make up 99 percent of all minerals on Earth.

BACKGROUND:  Scientists have identified over 2000 different minerals in the earth's crust. 95% of the earth's crust is composed of about a dozen different rock-forming minerals.

A. What is a mineral? All natural earth materials are made of minerals or a combination of minerals. Minerals are the building blocks of rocks. To be called a mineral it must have the following 5 characteristics:

Mineral characteristics #1 – Naturally Occurring Occurs naturally not artificial or man-made These are processes that occur on or inside Earth with no input from humans.

Mineral characteristic #2 - Solid All solids have a definite volume and shape. not a liquid or a gas Platinum (It might take two billion tons of ore to produce one pound of platinum!)

Mineral Characteristic #3 Definite chemical composition Only write blue! Made of one or more elements. Element Some minerals like gold or silver are made of only one element. A substance such as iron, oxygen, and gold which cannot be separated or broken down by ordinary chemical methods. All the elements are listed on the periodic table. For example: Gold = Au or Lead = Pb) Compound: Other minerals are combinations of two or more elements which are chemically combined. For Example Quartz = SiO2 Calcite = CaCO3 Image from http://channel.nationalgeographic.com/staticfiles/NGC/StaticFiles/Images/Show/38xx/382x/3822_history-of-gold-4_04700300.jpg Image from http://periodictable.com/Samples/082.28/s12s.JPG Image from http://skywalker.cochise.edu/wellerr/mingem/gemtp/smokyquartz/6xx-smoky-quartz6-rakhi.jpg Image from http://www.minerals.net/mineral/carbonat/calcite/images/9salmon.htm

Mineral Characteristic #4 Crystalline solids Only write blue! Mineral Characteristic #4 Crystalline solids Atoms arranged in an orderly pattern (Crystals) Crystalline means that atoms are arranged in a pattern that is repeated over and over again. For example, graphite’s atoms are arranged in layers and halite's are arranged in cubes. The crystal system a mineral has can help a geologist identify the mineral. Brain pop

Mineral characteristic #5 Abiotic (nonliving) or Inorganic Not alive and never alive This means that they aren’t made by life processes.

B. Crystals come from two places:

1. Crystals from Magma When magma cools slowly, the crystals that form are generally large enough to see with the unaided eye. When magma cools rapidly, the crystals that form will be small.

2. Crystals from solutions Crystals also can form from minerals dissolved in water. When water evaporates, minerals left behind come together to form crystals.