Stage 1 Desired Results Content Standard(s): Describe and classify minerals based on their physical properties.

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1 Lesson Title: Minerals Discipline Focus: Mineral Identification Grade level: 6 Length of lesson: 45 minutes Stage 1 Desired Results Content Standard(s): Describe and classify minerals based on their physical properties Construct reasonable explanations based on evidence collected from observations or experiments. Understanding (s)/goals Students will understand: Rocks are key materials to understand earth processes Compositions of rocks can vary and are defined by minerals Minerals and rocks are unique earth materials Minerals have many different properties Essential Question(s): What is a mineral? How are rocks and minerals different? How do we identify minerals? What are the different properties of minerals? Student objectives (outcomes): Students will be able to: Distinguish between rocks and minerals Identify mineral properties Test a sample to determine its correct mineral name Performance Task(s): Mineral quiz students have to identify unknown minerals using their knowledge of properties Stage 2 Assessment Evidence Other Evidence: Observations list and chart Informal student responses (i.e. shaking head yes or no)

2 Learning Activities: Stage 3 Learning Plan Materials: Baking ingredients (flour, sugar, chocolate chips, etc.) separated into cups or bowls (one of each for each student) Cookies Mineral sets Porcelain streak plates Glass plates (always keep on flat surface!) Nails Pennies Dilute acid (HCl) Hand lenses/magnifying glasses Minerals Lab Observations worksheets How to Identify Minerals handouts Unknown minerals table handouts Mineral Properties cheat sheet handouts (5 minutes) Introduction: Much of what we know about earth systems is from studying rocks. We need to understand how rocks are different to understand how they might form in different ways. A rock s composition (what it is made of) is unique to that rock. Minerals make up a rocks composition. Therefore, it is important to know and identify minerals. Baking Observations: Hand out baking ingredients and Minerals Lab Observations worksheets (see attached form) Students write down observations on worksheet As a class write down observations on the board group observations into categories as they are written (i.e. taste, smell, feel, color, etc.) (10 minutes) Mineral Observations: Hand out unknown mineral samples Students write down observations on same Observations worksheet except they try to use the categories listed on the board (new categories can be created) As a class write down observations on the board group observations into categories as they are written (similar to the baking ingredients) Relate baking goods to minerals and cookies to rocks: specifically address how each ingredient in a baking item is like elements or molecules in a mineral and different mixtures of baking items result in different kinds of cookies (rocks)

3 (10 minutes) Introduce Mineral and Mineral Properties: Mineral is a naturally occurring, inorganic solid formed through geological processes with a crystal structure and specific chemical composition. We use mineral properties to help us identify mineral samples. Go over handout, How to Identify Minerals (see attached form) Demonstrate how to test for different properties have students volunteer to demonstrate (15 minutes) Practice Identifying minerals Hand out unknown minerals table and Mineral Properties cheat sheet (see attached forms) Hand out different minerals from above with number labels (make sure to have a key of the numbers and associated mineral names) Students test for the properties and use the Mineral Properties cheat shee to find the name of the sample Students have to have their answers checked by teacher (5 minutes) Clean up Enjoy cookies!

4 Baking Material Observations: Graduate Fellows in K-12 Education MINERALS LAB OBSERVATIONS Mineral Observations:

5 How to Identify Minerals Definition of Mineral: a naturally occurring solid formed through geological processes. Characteristics of a mineral What makes a mineral a mineral? 1. Occurs through natural processes 2. Inorganic (not living) 3. Crystal structure 4. Homogenous solid 5. Characteristic chemical composition Physical Properties of Minerals: HARDNESS How well a mineral can resist scratching -Mineral hardness in ranked on a scale of 1-10 based on Moh s Hardness Scale COLOR LUSTER TRANSPARENCY STREAK CLEAVAGE / FRACTURE CRYSTAL SHAPE SPECIAL PROPERTIES The way a mineral interacts with light -Be careful! The same mineral can be many different colors. How the mineral surface looks in light -Metallic = shiny like metal -Non-metallic = Does NOT look like metal Vitreous = shiny like glass Dull or earthy = no shine Greasy, waxy, pearly, etc. How light passes THROUGH a mineral -Transparent = light passes through easily -Translucent = some light passes through -Opaque = no light passes through Color of mineral s powder left on a white porcelain streak plate Way the mineral breaks along weak bonds between atoms -Basal (sheety) = 1 direction of breaking (into sheets) -Tabular = 2 directions of breaking (90 to each other) -Cubic = 3 directions of breaking (90 to each other) -Rhombic = 3 directions of breaking (NOT at 90 to each other) -Conchoidal fracture = breaks in curved pattern -Massive fracture = no clean/clear direction of breaking Shape in which crystals of a mineral grow -Bladed/fibrous = looks like long fibers or blades -Hexagonal prism = 6-sided prism shape -Fizzes when dilute acid (HCl) is dropped on mineral surface -Unique tastes and smells! -Magnetic

6 Moh s Hardness Scale: measurement of relative hardness of materials Hardness of Common Objects Fingernail Copper Penny 3.5 Geologic Hammer 5.1 Knife Nail 5-6 Glass Plate Porcelain Streak Plate 6 Hardness of Some Minerals Talc 1 Gypsum 2 Calcite 3 Fluorite 4 Apatite 5 Orthoclase 6 Quartz 7 Topaz 8 Corundum 9 Diamond 10

7 Mineral Number Graduate Fellows in K-12 Education Hardness Color Luster Transparency Streak Other: Cleavage, Fracture, Crystal Shape, Special Properties Mineral Name

8 Mineral Name Hardness Color Luster Transparency Streak Cleavage/ Fracture Calcite 3 Clear or Vitreous to Transparent Rhombic 3 white dull directions Crystal Shape/ Habit Rhombohedral Special Properties Fizzes to acid (HCl) Quartz 7 Many Vitreous Transparent, translucent or opaque No cleavage Conchoidal fracture Hexagonal prism (6 sides) Olivine 6.5 Green to yellowgreen Potassium Feldspar 6 Many commonly white or pink Vitreous Vitreous to dull Transparent to translucent Translucent to opaque No cleavage May have conchoidal fracture Tabular 2 90 Massive to granular May be tabular Looks like green sand Plagioclase Feldspar 6 Many commonly white or gray Vitreous to dull Translucent to opaque Tabular 2 90 May be tabular Striations: fine parallel lines on surface Hornblende 5-6 Black to dark green Vitreous to dull Opaque Brown to gray/ 2 directions (60 and 120 ) Fibrous/bladed Cleavage angles are important

9 Mineral Name Hardness Color Luster Transparency Streak Cleavage/ Fracture Pyroxene 5-6 Black to Vitreous to Opaque Greenish 2 directions (87 to dark dull white/ 90 ) green Crystal Shape/ Habit Short, prismatic crystals Special Properties Cleavage angles are important Muscovite Mica Clear Vitreous to pearly Biotite Mica Black to Vitreous to brown pearly Halite 2.5 Clear to Vitreous to white pearly Transparent/ translucent Transparent to translucent Transparent to translucent White Basal 1 direction in sheets Basal 1 direction in sheets Cubic 3 90 Platy to massive Platy to massive Cubic Tastes like salt Gypsum 2 Many Silky to vitreous Transparent, translucent to opaque White Poor hard to see Bladed/ fibrous to massive Pyrite Gold to yellow Hematite Red, brown, black Graphite 1-2 Blackgray Fluorite 4 Manycommonly purple Metallic Opaque Black Poor hard to see Cubic Fool s gold Metallic to earthy Opaque Red No cleavage Massive Dense Metallic Opaque Gray No cleavage Massive Greasy feel Vitreous Translucent to transparent White Octahedron - 4 directions Massive

10 Mineral Name Hardness Color Luster Transparency Streak Cleavage/ Fracture Crystal Shape/ Habit Special Properties Talc 1-2 White, Pearly Opaque Basal 1 direction Massive Soapy feel pink, green Sulfur Yellow Dull Opaque Yellow No cleavage Massive Smells like hardboiled eggs Malachite 3-4 Light and dark green Galena 2.5 Silvery gray Dull Opaque Light green Metallic Opaque Grayblack Poor hard to see Massive Cubic 3 90 Cubic to octahedron Dense! Magnetite Black Metallic Opaque Black No cleavage Massive Magnetic