MINERALS
DO NOW TASK Look at the minerals and the tools inside the container. Based on their characteristics, attempt to place them (classify) in two separate groups!
We use rocks & minerals every day…
What are Minerals?
Minerals are: A single element S = Sulfur or C = Graphite Two or more elements chemically combined SiO2 = Quartz NaCl = Halite
They are also: Naturally occurring- NOT man made! Inorganic – Never once living Crystalline – Definite internal arrangement of atoms!
MINERAL OR NOT?
How to Identify Minerals:
1. Color The COLOR of the mineral!!!!!
Sulfur
Olivine
Potassium Feldspar
Calcite comes in many different colors.
WHICH IS GOLD?
WHY DO I NEED MORE THAN COLOR?? Many minerals have similar colors! A single mineral may have multiple colors!
White minerals: Talc Gypsum Quartz Calcite
2. Streak Test The color of the mineral fragments when ran across a ceramic plate
How is using a pencil a streak test? What mineral is used in a pencil?
What is the difference?
3. Luster Metallic Non-Metallic The way a mineral reflects light Metallic or non-metallic Metallic Non-Metallic
4. Moh’s Hardness Scale – A minerals resistance to scratching
Which mineral will scratch the other? GALENA (2.5) vs OLIVINE (6.5)
5. Cleaving vs. fracture – The way a mineral breaks
If the mineral Cleaves: It breaks along even planes.
If the mineral has fracture: Broken pieces are jagged and irregular
6. Hydrochloric (HCl) Acid test on Calcite Fizzes on contact