MINERALS Diamonds are forever…
What are minerals? • Silently record your initial thoughts about what a mineral is on your paper. • Now discuss with your neighbor your answer. Do you have any things in common? • Watch the video clip on the next slide and record the definition they give in your notes.
What are minerals? • The video defined a mineral as a naturally occurring, inorganic compound, with a definite composition and structure. • Here’s another way to describe minerals: • A mineral is a naturallyformed, inorganicsolid with a crystalline structure. • These 4 characteristics are true of all substances considered minerals. • Minerals are the building blocks of rocks. Rocks are not the same thing as minerals.
The 4 Characteristics #1 • Minerals must be made in nature – they can’t be made by people and considered a true mineral. • All minerals contain one or more of the 92 elementspresent in the Earth’s crust. • Minerals have predictable chemical formulas. Au Emerald = Be3Al2(SiO3)6
The 4 Characteristics #1 • How do minerals form on Earth? • Discuss this with your table group. Come up with some ideas. Be ready to share. • Magma (hot liquid rock) from deep inside the Earth rises and cools before reaching the surface • Magma heats up underground water sources, causing dissolved minerals to crystallize • Minerals crystallize at the bottom of lakes and seas • Seawater evaporates leaving mineral crystals behind
The 4 Characteristics #1 Halite (rock salt) that has formed in Death Valley, CA where water evaporates quickly
The 4 Characteristics #1 Magma inside the Earth can slowly melt its way through solid rock and Minerals crystallize in the process
The 4 Characteristics #2 • Minerals must be inorganic – this means that they aren’t made of living or once living things Am I a mineral? X Bones are organic – they were once part of a living being (they contain minerals, but are not minerals)
The 4 Characteristics #3 • Minerals must be solid. So, water is not a mineral, but naturally forming ice is.
The 4 Characteristics #4 • Minerals must have a crystalline structure. • This means that the atoms or compounds that make up the mineral have a repeating pattern that creates a distinctive crystal shape.
The 4 Characteristics #4 • Draw and name the following crystal shapes (systems): (Zircon) (Feldspar) (Topaz) (Gold) Which crystal shape if your favorite? orthorhombic (Emerald) (Gypsum) (Ruby)
The 4 Characteristics #4 (Gold) (Zircon) (Feldspar) (Topaz) (Emerald) (Ruby) (Gypsum)
The 4 Characteristics #4 • The size and shape of a crystal depends on the conditions where it forms - things like temperature, pressure, impurities and the amount of space it has to grow. • To increase their value, mineral crystals need to be cut and polished. (we’ll learn more about this later).
The 4 Characteristics #4 Both are made of pure carbon • The structure of a crystal influences how a mineral reacts to electrical forces and light, its hardness, its color, and how quickly it conducts heat. Diamond Graphite
Types of Minerals • Chemical compositionis a typical way to classify minerals into groups. • There are two big groups: • Silicate minerals = minerals that have both silicon (Si) and oxygen (O) as part of their chemical formula (90% of the minerals in the Earth’s crust) • Nonsilicate minerals = minerals that do not have both silicon and oxygen as part of their chemical formula
Gemstones • As the video said, minerals with well-formed crystals are considered semi precious. • Gemstones are typically minerals that are rare, beautiful, and hard, capable of being used in jewelry. • Gemstones can be precious or semi precious. The four precious gems are: diamond, ruby, emerald, and sapphire. • Sometimes gemstones are made of rock or organic material (pearls or amber).
Gemstones • Here are the traditional gemstones used to celebrate the number of years of marriage.
What is a mineral? • Tell your neighbor two of the four characteristics that are true of all minerals. Have your neighbor tell you the other two characteristics. • Discuss the most interesting thing you learned today. • Draw the letter of the day and write one sentence summarizing something important from today’s presentation. • What questions do you have right now about minerals? Record them at the bottom of this page. • Share your questions with your neighbor. Do you have any shared wonderings? Can you answer anybody’s question?
Video Source • All clips from: Earth Science for Students: Minerals, Gems, and OresEducational Activities, 2000 . Full Video.Discovery Education. Web. 16 March 2014. <http://www.discoveryeducation.com/>.
Image Sources • Slide 1: http://famousdiamonds.tripod.com/starofafrica2.jpg • Slide 1: http://famousdiamonds.tripod.com/starofafrica.jpg • Slide 1: http://media1.gameinformer.com/imagefeed/featured/mojang/minecraft/steve/steveminecraft_610.jpg • Slide 5: http://financesonline.com/top-10pgold-producing-countries-in-the-world/ • Slide 5: http://old.irocks.com/render.html?id=J11-29 • Slide 7: http://geologycafe.com/images/devilsgolf1.jpg • Slide 8: http://astro.wsu.edu/worthey/earth/html/im-resources/ore-vein-formation.gif • Slide 9: http://pitchingtheworld.files.wordpress.com/2012/06/4170bone.jpg • Slide 10: http://mycitymusings.files.wordpress.com/2013/01/ice_crystals.jpg • Slide 11: http://callisto.ggsrv.com/imgsrv/FastFetch/UBER2/00160082 • Slide 12: http://callisto.ggsrv.com/imgsrv/FastFetch/UBER2/00160082 • Slide 13: http://nevada-outback-gems.com/prospect/gold_specimen/octagonal_gold.jpg • Slide 13: http://www.daviddarling.info/images/zircon_crystals.jpg • Slide 13: http://www.healthstones.com/mineraldata/mineraldirectory/f/feldspar/feldspar.jpg • Slide 13: http://www.healingcrystals.com/images/Topaz-Crystals---Imperial-Topaz-Points-Brazil-07.jpg • Slide 13: http://johnbetts-fineminerals.com/jhbnyc/gifs/53100det.jpg • Slide 13: http://www.newark.osu.edu/facultystaff/personal/jstjohn/Documents/Common-minerals/Gypsum_files/image005.jpg • Slide 13: http://www.allaboutgemstones.com/images/gems_ruby_crystal_system_habit.jpg • Slide 14: http://www.all-color-gem-stones.com/images/gemstones-cuts-shapes.gif • Slide 15: http://upload.wikimedia.org/wikipedia/commons/f/f9/Diamond_and_graphite.jpg • Slide 19: http://www.restorejewelry.com/birthstones.png • Slide 20: http://www.restorejewelry.com/aniversarygifts.png • Slide 22: http://www.list-of-birthstones.com/February%20Birthstone.html