What Is an Advantage and a Disadvantage to Using Color to Identify a Mineral?
Action Type:
Minerals are naturally occurring, not-living compounds of elements. They are the building blocks of rocks. Geologists are greatly interested in minerals because they tin can reveal an enormous amount about the history of the geologic environment in which they are establish. For example, minerals rich in iron and magnesium are typically associated with volcanic processes. Geologists tin classify and identify minerals by observing various properties such equally streak, hardness, luster and, in some cases, fluorescence.
In this activeness, students will examine ten mineral specimens and explore the different properties that minerals exhibit. Students will record their observations on the samples' backdrop of luster, streak, hardness and fluorescence and use these observations to identify the minerals.
Grade Level: sixth – eighth Grade
Subject field Thing: World Science
National Standards: NS.5-viii.1, NS.5-8.3
[attach rockstars]
In 1968, the New Jersey Senate decreed the boondocks of Franklin a geological wonder: "The Fluorescent Mineral Capital of the World." Over 350 dissimilar minerals have been establish in the area, ninety of which glow brilliantly nether ultraviolet low-cal. Franklin, NJ, boasts two mineral museums devoted to fluorescing rocks, the region'due south unusual geology and its zinc mining history.
Activity Materials
The post-obit materials are available from Ward's Scientific Supply Visitor – http://wardsci.com. In order to reduce costs, ane – 2 sets of mineral specimens or materials tin can be purchased and prepare up as rotating grouping activities.
Mineral specimens needed:
Quartz
Plagioclase feldspar
Orthoclase feldspar
Calcite
Galena
Magnetite
Fluorite
Gypsum
Halite
Sulfur
Pyrite
Materials needed:
Streak plates – i.e., obviously white porcelain plates without any glaze or enamel. Alternatively, you lot can utilise the back, unglazed sides of regular bathroom or kitchen tiles. Yous need one for each student or group of students.
Glass plates – a few centimeters thick to avoid breakage. If yous don't want to order them, you can find them in thrift shops or dollar stores. You lot need 1 for each pupil or group of students
Pennies – one for each student
Steel nails – i for each pupil
Magnifying lens – one for each student or group of students
One or two small manus-held ultraviolet lights that students can laissez passer around.
One small-scale bottle of correction fluid
One ultra-fine point permanent marker
Vocabulary
Mineral: non-living compounds of elements that are found just in nature.
Rock: a solid mixture of one or more minerals.
Crystal: a solid whose atoms are bundled in an orderly, repeating pattern.
Fluorescence: the emission of light by a substance that has captivated calorie-free or other electromagnetic radiations of a different wavelength.
Luster: the style in which a mineral shines or reflects light.
Streak: the color that a mineral leaves when rubbed across a porcelain plate, known every bit a streak plate.
Hardness: a measure of a mineral'due south resistance to existence scratched by a tool or some other mineral.
What to Practise:
Prep: Label each mineral according to the list beneath by applying a very small amount of correction fluid on the mineral first before using a permanent marker to label each mineral with the appropriate number. Use your copy of the Mineral Identification Workshop to keep this list equally your answer key for the terminate of the activeness.
1 – Pyrite
ii – Galena
three – Calcite
4 – Fluorite
5 – Sulfur
6 – Magnetite
vii – Plagioclase feldspar
8 – Orthoclase feldspar
9 – Gypsum
ten – Halite
Recommendation: Set workstations or split students into groups, based on the number of sets of mineral specimens bachelor.
1. Begin the lesson by having the students scout the Science Friday Video, "Rock Stars." Discuss with students what they know near rocks and minerals. Review the definitions of and differences between rocks and minerals.
two. Inform students that they are going to explore minerals by observing the properties of 10 mutual minerals. Based on their observations, students will endeavour to place each mineral.
3. Inform students that in the procedure of identifying the minerals, they will be observing iv main properties (luster, streak, hardness, and fluorescence) of each specimen. Review the following backdrop and instructions with students:
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Luster is the style that a mineral reflects light or shines. If a mineral shines like metal, then the mineral is said to have a metallic luster. If a mineral does non shine like metal, information technology is said to have a non-metallic luster. Record metal or not-metallic luster for each mineral.
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Streak is the color of a mineral in its powdered form. To observe this characteristic, rub the mineral beyond the streak or porcelain plate, and observe the color left backside. Record the color of each mineral.
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Hardness is the measure of a mineral's resistance to being scratched. To test how difficult a given mineral is, scratch a common item (e.yard., drinking glass plate, fingernail, steel nail, or penny) confronting the mineral. Then scratch the mineral against the common item. Tape which item gets scratched by the mineral.
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Fluorescence is a mineral's ability to glow nether ultraviolet light. To perform this test, hold the mineral under a small ultraviolet light lamp. Record if the mineral glows and the color of the glow for each mineral.
iv. Have students rotate amidst the materials and mineral specimens to discover and record the properties of each of the minerals. Make sure students are recording their observations specifically for the mineral that they are examining.
v. Once observations are completed, have students compare and contrast their observations. Were they surprised by any of the results? If and so, why? Did they notice any properties that were not expected? How could these properties help them tell autonomously dissimilar minerals. Invite students to create a "guidebook" of the unlike minerals they observed, with clues for helping amateur geologists tell them apart based on the properties they observed.
What's Happening?
Minerals have many dissimilar physical backdrop. Scientists utilise these properties to help them classify and identify minerals. In this activity, students focus on observing four simple backdrop of minerals – luster, streak, hardness, and fluorescence.
Luster indicates how much light is reflected from a mineral's surface. An example of a mineral with metallic luster is pyrite, which shines similar gold metal. An example of a mineral that has a not-metallic luster is quartz, which resembles an ordinary piece of glass.
Streak refers to the color that a mineral leaves in a powdered class; it indicates the true color of the mineral. For example, the mineral pyrite may appear yellow to the eye. But when rubbed on a white porcelain plate (called a streak plate), pyrite leaves a black streak. Identifying a mineral by its streak is a much more authentic method than identifying a mineral by its colour to the eye.
Hardness is a measure of a mineral's resistance to being scratched. Scientists utilize a numeric scale (called the Mohs scale) of one to ten to allocate minerals by hardness. For example, the softest mineral, talc, rates every bit 1 and the hardest mineral, diamond, rates as 10.
Fluorescence is a mineral's ability to glow when exposed to ultraviolent light. This happens when the chemicals within the mineral react in response to the ultraviolet lite. Some common minerals that are known to fluoresce are calcite and willemite. Respectively, these minerals fluoresce crimson-orange and green. In mines or caves, fluorescence can be used to discover certain mineral deposits.
Topics for Science Class Word
• What are some uses of minerals? What are some advantages and disadvantages of using minerals?
• How are crystals and minerals related?
• What are the differences between fluorescent rocks and phosphorescent rocks?
Extended Activities and Links
Extend the activity past having students use other tools to find boosted properties. For example, they can employ magnets to decide which minerals are magnetic, or drops of vinegar to observe which minerals effervesce in reaction to the acid in vinegar. Students also tin can classify minerals based on their smell and weight.
Have students become on a rock collection hunt in their surrounding neighborhood. Students tin can discover properties, identify rocks or minerals and nowadays their findings to the class.
Conduct an interactive virtual lab on minerals:
http://glencoe.mcgraw-hill.com/sites/0078778026/student_view0/unit1/chapter3/virtual_lab.html
View an online guide to rocks, minerals, and gemstones: http://world wide web.minerals.net/
Explore mineral-related activities online:
http://www.sdnhm.org/kids/minerals/index.html
View a fluorescent-mineral photo gallery:
http://users.ece.gatech.edu/~hamblen/uvminerals/
Inquiry other places in the United States likewise Franklin, NJ, where fluorescent minerals are found. What kind of minerals are they?
Consider a pupil field trip to see minerals. Find out if your local scientific discipline or natural history museum has a mineral collection. For case, if yous live in the New York metropolitan area or Connecticut, there are spectacular collections at New York Urban center'south American Museum of Natural History and the Yale Peabody Museum of Natural History in New Haven, CT. If you live in Arizona, consider taking students to the annual Tucson Gem and Mineral Show in Feb.
This lesson plan was created by the New York Hall of Science in collaboration with Science Fri as part of Teachers Talking Science, an online resources for teachers, homeschoolers, and parents to produce costless materials based on very pop SciFri Videos to help in the classroom or around the kitchen table.
The New York Hall of Science is a science museum located in the New York City borough of Queens. NYSCI is New York City's but hands-on science and technology center, with more than 400 hands-on exhibits explore biology, chemistry, and physics.
Source: https://www.sciencefriday.com/educational-resources/mineral-madness/