Help with science fair
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Help with science fair
My daughter is during a science project about rocks. “Which Rock Is Harderâ€
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- Former Expert
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If you do a search for "rock hardness scale" using your favorite search engine you will get some entries that have "Mohs Scale of Hardness" one of which is http://www.bestcrystals.com/hardness.html
This scale is based on what can scratch what and goes back to the early 1800's and Frederick Mohs.
The problem with impact tests or drop/shatter tests is they tend to measure how brittle a substance is. Things can be quite hard (scratch resistant) and be extremely brittle. Glass is a good example.
This scale is based on what can scratch what and goes back to the early 1800's and Frederick Mohs.
The problem with impact tests or drop/shatter tests is they tend to measure how brittle a substance is. Things can be quite hard (scratch resistant) and be extremely brittle. Glass is a good example.
-Craig
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- Joined: Thu Nov 15, 2007 2:52 pm
Thanks craig for the information. I purchased the kit and a collection of all three types rocks. However, I don't have a diamond, ruby,or opal to conduct the hardness experiment so is there there some other method I may use to prove my point?
I don't know how to proceed with what I have. I have to conduct an experiment that I can show on my presentation board. Please give me an idea.
Catherine
I don't know how to proceed with what I have. I have to conduct an experiment that I can show on my presentation board. Please give me an idea.
Catherine
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- Former Expert
- Posts: 1297
- Joined: Mon Oct 16, 2006 11:47 am