The Lithosphere
1. The Lithosphere The lithosphere is the hard shell of the Earth, consisting of the crust and the topmost part of the upper mantle. It is an average of 100km thick. It contains the minerals, rocks and soils that humans have used for building materials, metals and agriculture.
Rocks Rocks are heterogenous solids composed of many minerals. The physical and chemical properties of rocks are not strictly defined. There are 3 types of rocks: Igneous Sedimentary Metamorphic
1. Igneous Rocks Formed when magma (molten rock) cools and solidifies eg: granite
2. Sedimentary Rocks Formed by the accumulation and compaction of debris at the bottom of lakes and oceans. Limestone is a sedimentary rock used in construction
3. Metamorphic Rocks Former igneous or sedimentary rocks that have been transformed by heat or pressure underground. eg: granite turns to gneiss eg: limestone turns to marble Rock Cycle
Minerals Minerals are solid inorganic substances with clearly defined composition and properties. In most minerals atoms are organized in the form of identically shaped crystals. Each mineral has its own distinct chemical composition. 4000 different minerals exist on Earth.
Examples of Minerals Gold (Au) Copper (Cu) Iron (Fe) Quartz (SiO2) Copper sulfate (CuSO4) ST EST AST Gold Ore Quartz
Classifying Minerals Minerals are classified according to the following 4 properties: Colour Transparency Hardness Streak
1. Colour Idiochromatic minerals have a characteristic colour. eg: azurite is blue Allochromatic minerals vary in colour. eg: quartz
2. Transparency Minerals are one of the following: Transparent (let light pass through) Translucent (let light through but blurred) Opaque (no light passes through)
3. Hardness Minerals are classified according to how hard they are. Mohs scale assigns a value from 1 to 10 to indicate a mineral’s hardness. Talc is soft and scores a 1 on Mohs scale Quartz scores a 7 Diamond scores a 10
4. Streak When a mineral is rubbed on a surface it leaves a powder streak that is a characteristic colour for that mineral. Identifying Minerals 7:54
Mining of Minerals
Mining of Minerals Minerals are extracted from rock ores which are mined from the lithosphere. Quebec is known for large deposits of gold, copper, zinc, and most recently diamonds. Once the ore is extracted, the mineral is separated from the rock by chemical and physical means.
Identifying Minerals Bonus Activity