260 likes | 276 Views
Learn about the characteristics of minerals, including their physical properties, chemical composition, and how to identify them. This article explores concepts such as color, streak, luster, cleavage, fracture, and hardness.
E N D
Key Concept #1 What is a mineral? inorganic naturally occurring A mineral is a definite chemical composition substance which has a What would be the opposite of this? man-made organic random composition ESRT Mineral Chart Click Here
Key Concept #2 The reason why minerals have different physical properties is due to their internal arrangement of atoms
Key Concept #2 An example of two minerals which have the same chemical composition but different physical properties is Click Here graphite & diamond
Key Concept #3 The Main Physical Properties Used to Identify Minerals A. Color 1. a poor indicator a. minerals can be multiple colors b. many minerals are the same color
One Mineral, Many Colors
Different Minerals Same Color
Key Concept #3 The Main Physical Properties Used to Identify Minerals B. Streak the powder form of a mineral more reliable than color
Key Concept #3 The Main Physical Properties Used to Identify Minerals C. Luster how light reflects off a mineral a. metallic b. non-metallic -looks like a metal -Leaves a dark (black, grey, green or brown) streak on a white streak plate -looks earthy, waxy, greasy or brilliant -leaves white or no streak on a black streak plate
Key Concept #3 The Main Physical Properties Used to Identify Minerals D. Cleavage -mineral breaks in a predictable pattern because of its arrangement of atoms -At least one distinct flat side when broken
Key Concept #3 The Main Physical Properties Used to Identify Minerals E. Fracture -the mineral breaks randomly -Irregular sides
Key Concept #3 The Main Physical Properties Used to Identify Minerals F. Hardness 1. resistance to being scratched- something softer than a material cannot scratch the harder material 2. It is NOT the same as breaking! For example: You can break glass easily with steel. However, steel will not scratch glass.
Key Concept #3 The Main Physical Properties Used to Identify Minerals Hardness MOH’S SCALE OF HARDNESS TALC ORTHOCLASE GYPSUM QUARTZ CALCITE TOPAZ FLUORITE CORUNDUM APATITE DIAMOND
Key Concept #4 Minerals have a definite chemical composition. The two elements by mass that make up the greatest percentage of the Earth’s crust are oxygen silicon
Key Concept #4 Minerals have a definite chemical composition. These two elements combine to form compounds called silicates (SiO4)
Key Concept #4 Minerals have a definite chemical composition. They combine in a specific structure called a: silicon-oxygen tetrahedra
REVIEW- WHAT IS A MINERAL? • A mineral is naturally occurring, inorganic, and crystalline solid having a definite chemical composition • Each mineral has its own distinctive crystal structure that can lead to a very accurate ID • All minerals are solids that are composed of one or more chemical elements
All minerals are rocks, but not all rocks are minerals nor are they all composed of minerals- the main reason: rocks can be organic like coal • Minerals form as the result of inorganic crystallization or by the re-crystallization of atoms in various rock-forming environments
Minerals can be identified by color, streak, luster, hardness, density, cleavage, crystal structure and other characteristics (ex. magnetism, response to hydrochloric acid, etc)