Welcome
Welcome to the Little Jerusalem EarthCache Series. This series was placed at the request of the Stae Park so it is important that you follow all rules to demonstrate how responsible geocachers are with the environment. Please stay on the trail and follow all rules as posted. This first EarthCache is done under specific direction of the state park as seen on the sign posted at GZ. At no point, should you touch, collect, or disturb the environment except where specifically directed. Please enjoy this series of EarthCaches responsibly. There is a $5 day fee to access this park.
Earth Science Lesson
Mohs Hardness Scale
Hardness and specific gravity are two of the major characteristics of rocks. Hardness of a rock or mineral is its resistance to scratching and may be described relative to a standard scale of 10 minerals known as the Mohs scale. F. Mohs, an Austrian mineralogist, developed this scale in 1822. At this location, you will be doing a quick experiment to determine the hardness of the Niobara Chalk sample provided by the state park. Do not try this at any other location. You will need three items or differing hardness to help determine the hadness.
Step1
Select three items of varying hardness.
Step 2
Scratch the Niobara Chalk sample in front of you.
Step 3
Make an observation based on the ability of your item to make a scratch.
Step 4
Record your observations and use them top answer the questions below.
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Niobara Chalk Experiment
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Material
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Hardness
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Piece of chalk
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1
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Plaster of Paris
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2
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Fingernail
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2.5
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Gold
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2.5-3.0
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Penny
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3.5
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Iron Nail
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4
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Window Glass
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5.5
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Steel File
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6.5
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Ceramic tile
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7.0
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Aluminum oxide
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9.0
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Logging Tasks
- How is hardness for rocks determined?
- Which three items did you use for this experiment?
- Which was the softest item that was able to scratch the chalk?
- Where does the Niobara Chalk rank on the Mohs Hardness scale?
References
- Education.com. (2013, April 26). The Mohs Test: How to Compare the Hardness of Minerals: Science project. Retrieved from https://www.education.com/science-fair/article/mohs-hardness-test-minerals/
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Mohs Hardness Scale. (2020). Retrieved from https://scienceviews.com/geology/mohs.html
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King, H. M., Dr. (2020). Mohs hardness scale. Retrieved April 05, 2021, from https://geology.com/minerals/mohs-hardness-scale.shtml
