Rocks and Minerals Junior Science
Feb 16, 2016
Rocks and Minerals
Junior Science
Rocks and Minerals
• Rocks may not be alive, but they can still tell us quite a lot about the past.
• Geology is the study of the Earth, its rocks, minerals, volcanoes, earthquakes, fossils etc.
• Mineralogy is a branch of geology that studies minerals.
Minerals• A mineral is a naturally
occurring substance with its own particular chemical composition & structure.
• Minerals are found in the Earth’s crust (lithosphere) in beautiful shapes called crystals.
• Quartz, mica and feldspar are examples of minerals.
• Minerals are the building blocks that make up rock.
Characteristicsof minerals
• Minerals have several characteristics or properties that help geologists differentiate between them:
• Crystal structure• Pigment and streak• Hardness
Crystal Structure
• Many minerals have a distinctive crystal structure
• Eg. Wulfenite has flat crystals
Rocks
• The study of rocks is a branch of geology known as petrology.
• A rock is made up of minerals. Granite is a rock made from three minerals—quartz, mica and feldspar.
Ores
• Ores are rocks or minerals that contain elements that may be extracted for profit.
• Iron, for example, is extracted from an ore called haematite.
• Aluminium is extracted from the ore bauxite.