GEOL 1301 - Lab 02 - Minerals

GEOL 1301 Name: Jonathan Venegas Minerals Lab Learning and Lab objectives: In this lab, you are learning to identify a set of common minerals and to sort minerals into their correct groups. Your lab instructor will review some of the common minerals, the physical properties we will use to identify these, and the techniques we will use to identify them based on these physical properties. Some helpful online resources can also be found in the Background Information section below. Please complete the two tables (Table 1: Examining and Classifying Minerals, and Table 2: Mineral Groups) and submit them as a single pdf with to your instructor online via Canvas. Do not forget to put your name on the worksheets! Important notice: In this lab you will be using hydrochloric acid (HCl). This is a dangerous liquid for skin and eyes, and it can also damage clothes. By starting this lab, you acknowledge that you have read and understood the dangers associated with HCl. If you do not want to use it, ask your lab instructor to use it for you. Background information on physical properties of minerals: A physical property describes the state of a physical system. In addition, this property is measurable and/or can be categorized. Some common examples you may be familiar with include boiling temperature, color, and density. In this case, we are interested in physical properties that are diagnostic of a mineral. Mohs’ Hardness Scale: This scale gives you a simple and practical way to assess the hardness of minerals via common objects you might have in your house. Hardness is a measure of how easily the surface of a mineral can be scratched. For example, if a copper penny scratches a mineral, the mineral is less than a 3-3.5 on the Mohs Hardness Scale (Table 3.2 in your textbook). For this lab, we will use the following materials:  Fingernail, 2-2.5  Copper penny, 3-3.5  Steel nail, 4.5  Glass plate, 5.5  Porcelain plate, 6.5 Crystal Habit and Form: Please see page 69 of your textbook. In addition, this page has excellent photographs of types of crystal habit and form: https://geology.com/minerals/crystal-habit/ Mineral Names and their physical properties: This page has a linked list of common mineral types: http://geology.com/minerals/ Mineral Lab: Part 1 1

You are given a set of 10 minerals for this lab in trays as samples. These samples include only the following minerals:  Calcite  Gypsum  Hematite  Hornblende  Muscovite  Olivine  Orthoclase  Pyrite  Quartz  Talc Note that the list above is not in the order that the samples are in the trays! Feel free to work in groups for this portion of the lab. Discussion amongst your peers is always a great help when you are conducting observational science! It is your task for this part of the lab to fill in Table 1 with the following information:  the physical property you observe for each sample (column 2-4),  any other properties that you observe that are of interest (column 5),  and the name of the mineral you believe the sample to be (column 6). 2

Mineral Lab: Part 2 Below is a list of mineral classes, based on their chemical formula. For this part of the lab, your task is to assign a class to each of the minerals listed in Table 2. Please review mineral classes on page 60 -65 of your textbook. Silicates: contain silicon (Si) and oxygen (O) Carbonates: metals plus CO 3 Sulfates: metals plus SO 4 Sulfides: metals plus S Oxides: metals plus O Hydroxides: metals plus OH Phosphates: metals plus PO 4 Halides: metals plus F, Cl, Br, or I Native Elements: one element only Table 2: Minerals and their mineral groups Mineral Name Formula Group Anhydrite CaSO 4 Sulfates Apatite Ca 5 F(PO 4 ) 3 Phosphates Barite BaSO 4 Sulfates Beryl Be 3 Al 2 Si 6 O 18 Silicates Chalcopyrite CuFeS 2 Sulfides Chromite FeCr 2 O 4 Oxides Copper Cu Native Elements Corundum Al 2 O 3 Oxides Fluorite CaF 2 Halides Galena PbS Sulfides Goethite FeO(OH) Oxides/Hydroxides Halite NaCl Halides Magnetite Fe 3 O 4 Oxides Olivine (Fe,Mg) 2 SiO 4 Silicates Plagioclase NaAlSi 3 O 8 to CaAlSi 2 O 8 Silicates Pyrrhotite FeS Sulfides Rutile TiO 2 Oxides Sphalerite ZnS Sulfides Sulfur S Native Elements Sylvite KCl Halides 4