Minerals ROCK! This presentation was made possible with funding from the PromoScience programme of NSERC ©McGill University 2010 Minerals Why are they important? ©McGill University 2010 Minerals are important because: We use them in everyday life! • Glass (Quartz) www.public-domain-image.com ©McGill University 2010 Minerals are important because: We use them in everyday life! • Glass (Quartz) • Lead in pencil (Graphite) www.public-domain-image.com ©McGill University 2010 Minerals are important because: We use them in everyday life! • Glass (Quartz) • Lead in pencil (Graphite) • Toothpaste (Fluorite) www.public-domain-image.com and www.wikipedia.org Public domain ©McGill University 2010 Minerals are important because: We use them in everyday life! • • • • Glass (Quartz) Lead in pencil (Graphite) Toothpaste (Fluorite) Coins and wiring (Chalcopyrite, from which most copper metal is made) www.public-domain-image.com and www.wikipedia.org Public domain ©McGill University 2010 Minerals are important because: We use them in everyday life! • • • • Glass (Quartz) Lead in pencil (Graphite) Toothpaste (Fluorite) Coins and wiring (Chalcopyrite, from which most copper metal is made) • White paint (Rutile and Ilmenite) www.public-domain-image.com and www.wikipedia.org Public domain ©McGill University 2010 Minerals are important because: We use them in everyday life! • • • • Glass (Quartz) Lead in pencil (Graphite) Toothpaste (Fluorite) Coins and wiring (Chalcopyrite, from which most copper metal is made) • White paint (Rutile and Ilmenite) • Make-up (Talc, Muscovite) www.public-domain-image.com, www.wikipedia.org, and wpclipart.com Public domain ©McGill University 2010 Minerals are important because: We use them in everyday life! • • • • Glass (Quartz) Lead in pencil (Graphite) Toothpaste (Fluorite) Coins and wiring (Chalcopyrite, from which most copper metal is made) • White paint (Rutile and Ilmenite) • Makeup (Talc, Muscovite) • Jewellery (Gold, Silver, Platinum…) www.public-domain-image.com, www.wikipedia.org, and wpclipart.com Public domain ©McGill University 2010 Minerals • How many minerals are there in the world? – Over 4200 different minerals! – But only 100 are common • Ones that are more rare include: Gold www.wikipedia.org Public domain Silver ©McGill University 2010 Rocks • Rocks are made of minerals • Granite is a rock made up of three main minerals: – Feldspar – Quartz – Mica ©McGill University 2010 A world of rocks • There are main types of rocks: – Igneous rocks – Metamorphic rocks – Sedimentary rocks www.wikipedia.org and www.usgs.gov Public domain Redpath Museum ©McGill University 2010 Igneous rocks • Deep in the earth the temperatures are so high that materials, including minerals, melt and form magma • When the magma cools, it becomes rock • E.g., granite, basalt www.wikipedia.org Public domain ©McGill University 2010 Metamorphic rocks (i) • When rocks are re-buried below the Earth’s surface and exposed to high pressure and temperature, the minerals become unstable and they exchange chemical elements • This forms new minerals This may also cause some grains to grow and others to shrink ©McGill University 2010 Metamorphic rocks (ii) • This process produces new types of rocks that are different in composition and texture from the originals • E.g., bands of minerals are folded in gneiss Gneiss www.usgs.gov Public domain Slate ©McGill University 2010 Sedimentary Rocks • Sediments come from the erosion of previously existing rocks, dissolved minerals that precipitate out of solution, or the remains of plants Sandstone and animals • Loose sediment accumulates in beds and, over time, becomes compressed and cemented together • These types of rocks are usually layered • E.g., limestone and sandstone www.usgs.gov Public domain Redpath Museum Limestone2 ©McGill University 2010 The Rock Cycle: Always Recycling Magma Crystallization Igneous rock Erosion Sedimentation Sedimentary rock Tectonic burial Metamorphic rock Melting of rock and minerals www.wikipedia.org Public domain ©McGill University 2010 Crystals Quartz Halite ©McGill University 2010 What is the difference between minerals, crystals, and rocks? (i) – Minerals are made up of regularly arranged atoms – Minerals grow as distinct objects called crystals Agate (a form of the mineral quartz) ©McGill University 2010 What is the difference between Crystals minerals, crystals, and rocks? (ii) – Crystals are made up of only one type of mineral – A crystal’s atoms, ions, or molecules are arranged in an orderly, repeating pattern – Crystals can have different shapes, depending on how the groups of atoms are arranged Quartz crystal and penny ©McGill University 2010 What is the difference between Crystals minerals, crystals, and rocks? (iii) – A rock is a mass of many crystals from one or several minerals – Granite is a rock made of main minerals: • Feldspar • Quartz • Mica ©McGill University 2010 How are crystals formed? • Most come from a liquid evaporating (e.g., salt) or magma cooling • Minerals in the liquid precipitate out as the liquid evaporates As more minerals precipitate out, the crystal grows in size • Crystals can grow forever, as long as they have the chemical elements and the environmental conditions necessary ©McGill University 2010 Mineral Identification (i) • The two most important properties that scientists use to identify minerals are: – chemical composition (e.g., via microprobe analysis) – crystal structure (e.g., via X-ray diffraction analysis), which is reflected in the mineral's crystal symmetry and shape ©McGill University 2010 Mineral Identification (ii) • Other properties that scientists use to help identify minerals include: – Colour – Luster (how the surface reflects light) – Streak (the mark it leaves on a ceramic plate) – Hardness – Magnetism – Crystal system (crystal shape and the way in which the crystals are arranged) ©McGill University 2010 Acknowledgments • Scientific consultation – Dr Jeanne Paquette (Earth and Planetary Sciences) – Dr Peter Tarassoff (Redpath Museum) • Concept, design, and production: – Jacky Farrell – Elizabeth Miazgy – This presentation was made possible with funding from the PromoScience programme of NSERC ©McGill University 2010 [...]... by geological processes – They can’t be man-made so steel is not a mineral www.wikipedia.org Public domain ©McGill University 2010 Minerals are inorganic – Not living and not made by living things – Shells are not a type of mineral but they they are made of solid materials (biominerals) similar to some inorganic minerals Redpath Museum ©McGill University 2010 A mineral is solid – Minerals may be dissolved...What is a mineral? • A mineral must have… – A crystalline structure – A definite chemical composition • A mineral must be… – Formed by geological processes – Inorganic – Solid ©McGill University 2010 What does this mean? • A mineral must have… – A crystalline structure • Minerals are made of molecules, and a crystalline structure is a repeated pattern of those molecules ©McGill University 2010 Crystalline... form a continental collision Some mountains (e.g., the Himalayas) form this way Wikipedia.org, USGS: public domain ©McGill University 2010 Rocks www.wikipedia.org Public domain ©McGill University 2010 Rocks • Rocks are made of minerals • Granite is a rock made up of three main minerals: – Feldspar – Quartz – Mica ©McGill University 2010 A world of rocks • There are 3 main types of rocks: – Igneous rocks... Is water a mineral? (i) www.usgs.gov Public domain ©McGill University 2010 Is water a mineral? (ii) • NO! – Inorganic – Naturally occurring – But it is a LIQUID and has NO CRYSTALLINE STRUCTURE www.usgs.gov Public domain ©McGill University 2010 How are minerals formed? • Many minerals crystallize from liquids, principally magma/lava (molten rock) , hot waters (e.g., geysers), or oceans • Others are... Metamorphic rocks – Sedimentary rocks www.wikipedia.org and www.usgs.gov Public domain Redpath Museum ©McGill University 2010 Igneous rocks • Deep in the earth the temperatures are so high that materials, including minerals, melt and form magma • When the magma cools, it becomes rock • E.g., granite, basalt www.wikipedia.org Public domain ©McGill University 2010 Metamorphic rocks (i) • When rocks are... when rocks are re-buried below the Earth’s surface and exposed to high pressure and temperature The minerals become unstable and they exchange chemical elements This forms new minerals ©McGill University 2010 Why are minerals found in large quantities in some places and not others? • The Earth’s surface is made up of plates that move “Plate tectonics” describe this motion • Together with erosion, plate... the Earth’s surface and exposed to high pressure and temperature, the minerals become unstable and they exchange chemical elements • This forms new minerals This may also cause some grains to grow and others to shrink ©McGill University 2010 Metamorphic rocks (ii) • This process produces new types of rocks that are different in composition and texture from the originals • E.g., bands of minerals are... concentrate some of these elements in bodies of rocks that can be mined • Plate tectonics are the Earth's giant "recycling engine“ Plate tectonics www.wikipedia.org Public domain ©McGill University 2010 The world’s main plates www.wikipedia.org Public domain ©McGill University 2010 Types of plate boundaries (i) • Transform boundaries: plates grind past each other along a transform fault (e.g San Andreas... are not liquid www.wikipedia.org ©McGill University 2010 Is ice a mineral? (i) www.usgs.gov Public domain ©McGill University 2010 Is ice a mineral? (ii) • YES!! – Inorganic – Solid – Crystalline structure – As long as it is naturally occurring, ice is considered a mineral Ice in your ice-cube tray is not naturally occurring: ice in a glacier is www.wikipedia.org Creative Commons Attribution-Share Alike... one plate moves underneath the other, it forms a subduction zone Deep marine trenches, volcanoes, and some mountain chains (e.g., the Andes) form in these areas Caribbean plate North American plate The Puerto Rico trench Wikipedia.org, USGS: public domain ©McGill University 2010 Types of plate boundaries (iv) • Convergent boundaries (cont’d): – If the two plates collide and both contain continental crust,