In person lab 1- Minerals and Rocks-2 redone

GEOL 102 History of the Earth S23 Name: Emanuel Moreno In person lab 1: Minerals & Rocks Purpose: Minerals are the building blocks of our world, and rocks are made of up minerals. These are materials that both make up the Earth around us and are important resources used in our everyday lives. By learning to identify a few key minerals and rocks through practicing minerals and rocks in person, and understanding the context of how and where they form, you can approach the world from a very different perspective, eyes wide open to the “how” and “why” of your surroundings. This lab is based on one by Madeline Marshall, Albion College Tasks: ◻ Work to explore and identify the minerals, igneous rocks, sedimentary rocks, metamorphic rocks, and tell a story of the rock cycle. ◻ This should be a review for you based on your work in Geology 100, but please ask lots of questions! Due: end of your lab period Part A: Minerals 1. Complete this blank Bowen’s Reaction Series with the range of temperatures that these minerals crystallize at, and the mineral names themselves. 2. Then, review the physical properties outlined below. Examine the minerals for this lab and use the physical properties, along with the minerals reference table to identify them all. 1A – Biotite 2A – Muscovite 3A – Plagioclase Feldspar 4A – Quartz 5A – Potassium Feldspar 6A – Pyroxene 7A –Olivine 8A – Amphibole 9A – Calcite 10A – Pyrite 3. Add the appropriate number of the sample to the names you placed on the Bowen’s diagram. 1

GEOL 102 History of the Earth S23 4. There are two samples that aren’t part of Bowen’s Reaction Series, because they don’t form through igneous processes (in volcanoes or magma chambers). Identify these two minerals by name below, and note 1 key identifying characteristic of each (how did you figure it out?): Calcite – 9 rhombohedral cleavage Pyrite – 10 brassy yellow color Most common minerals can be identified by their physical properties, which result from the internal arrangement of atoms in the mineral. These properties include: ● Color : fairly obvious, but can vary widely and is generally not to be trusted as the only criterion 2

GEOL 102 History of the Earth S23 ● Luster : how shiny, dull, metallic, waxy, glassy, or resinous does it appear? ● Cleavage : this is how a mineral naturally breaks apart along flat surfaces; imagine that a mineral is like a LEGO castle – you can break it down into its component parts (LEGOs), which all have flat sides that were previously concealed when all stuck together – those flat sides are what we call cleavage planes ● Shape (crystal form): this is how a mineral grows, and often is a common geometric shape, like a cube, rhombohedron, octahedron, or dodecahedron ( it’s the shape of the LEGO castle from above ) ● Hardness : how hard is your mineral? This can be determined by figuring out what standard object can scratch it, and what it can scratch – we use the Mohs hardness scale, from 1(talc) to 10 (diamond). ● Reaction with acid : some minerals, especially calcite, will react with a weak hydrochloric acid and produce bubbles (and CO2) ● Smell, Taste : the fun ones, which can help you determine minerals like halite (aka table salt) or sulfur (smells like rotten eggs) Types of Mineral Cleavage (and examples) Minerals Reference Table Luster Colors Cleavage / Fracture Hard- ness Other Uses Composition Name Metallic Brassy yellow fractures 6.5 crystals cubic or octahedral, striated Sulfur ore FeS 2 Pyrite (fool’s gold) Non- metallic Color-less to white or yellow 1 cleavage plane 2-2.5 Flexible sheets, shiny Paint, roofing, cosmetics KAl3Si3O10(OH) 2 Muscovite mica Black to dark brown 1 cleavage plane 2.5-3 Flexible sheets, shiny Construction materials K(Mg,Fe)3AlSi3O 10(OH)2 Biotite mica Colorless to 3 cleavage planes 3 Fizzes with Cement, lime, CaCO3 Calcite 3

GEOL 102 History of the Earth S23 variable (rhombohedral) HCl acid, rhombohedral construction Black to dark green 2 cleavage planes at 90º 5-6 Jewelry (Ca,Na) (Mg,Fe,Al) (Si,Al)2O6 Pyroxene Black to dark green 2 cleavage planes at 120º 5-6 Usually relatively long crystals Jewelry NaCa2(Mg,Fe,Al) 5(Al,Si)8O22(OH) 2 Amphibole White to pink 2 cleavage planes at 90º 6 Often blocky crystals Ceramics, glass KAlSi3O8 Potassium feldspar White to gray 2 cleavage planes at 90º 6 Striations on surfaces Ceramics, glass (Na,Ca)AlSi3O8 Plagioclase feldspar Green to gray or brown fractures 6.5 Granular, commonly light green Furnace bricks, gemstone (Fe,Mg)2SiO4 Olivine Colorless to variable fractures 7 Glassy, can form hexagonal crystals Glass, electronics, jewelry SiO2 Quartz Dark red to green fractures 6.5-7.5 crystals cubic or dodecahedra Gemstone, abrasives Fe3Al2Si3O12 Garnet Part B: Igneous Rocks Magma and Lava are often used cavalierly in everyday speech, but those terms actually refer to pretty different things. Magma is molten material inside the earth, and when this intrusive material crystallizes into rock, the crystals will be large due to the gradual cooling process. Lava has been erupted onto the surface of the earth (sometimes on land, sometimes at the ocean floor), and when this extrusive material crystallizes into rock, the crystals will be tiny due to the rapid cooling or quenching process as it hits much cooler air or water. 1. Identify the samples of igneous rocks. Utilize the identification chart below to help. B1 – basalt B2 – pumice B3 – andesite B4 – andesite B5 – diorite B6 – granite B7 – rhyolite B8 – andesite 2. Place their names and the corresponding sample numbers on the diagram below showing both location of formation within or above the Earth AND the range of compositions . ( There is a one rock type seen in two different samples; include both #s .) 4