Rock Properties
What does hardness tell us about a rock?
It tells us how easy or difficult it is to scratch a rock.
What are the three main types of soil?
Sand, clay, and loam.
What is weathering?
Weathering is when wind or water slowly breaks down rocks over time.
Which rock would be the hardest:
Rock A: scratches glass
Rock B: Breaks in two during the shake test
Rock C: It scratches with a fingernail
A
What type of soil is gritty and is found on beaches?
sand
If a rock can scratch glass, how would you describe its hardness?
Very hard rock.
How does sand feel?
Gritty and rough like sandpaper.
How does wind change the land?
Wind can create patterns in dirt and sand, like ripples or sand dunes.
Which rock would be the softest:
Rock A: scratches glass
Rock B: Breaks in two during the shake test
Rock C: A steel nail will not scratch it.
B
What type of soil is sticky when it is wet, but it held water very well in our water retention lab?
clay
What is luster?
Luster describes how shiny or dull a rock looks.
Why is loam considered the best soil for growing plants?
It holds water and nutrients perfectly.
What effect does water have on rocks along coastlines?
Water wears away rocks, creating sea stacks and carving valleys.
How shiny or dull a rock is
What type of soil is a mixture of sand, clay, and organic matter?
loam
What does the Mohs Hardness Scale measure?
It measures how hard rocks are
What happens to clay when it gets wet?
It feels sticky.
What long-term changes does weathering cause to rocks?
Tall sea stacks become shorter, rock edges become smooth, and large rocks break into smaller pieces.
What is a rock's texture?
How the rock feels
If you wanted to find out what type of soil you have, what property would be most helpful?
-water retention
-color
-texture
-ability to grow plants
Texture
If Rock A is harder than orthoclase but softer than topaz, what can you infer about Rock A?
Rock A has a hardness between 6 and 8 on the Mohs scale.
How can you identify soil without tools?
By its texture, how it feels when you touch it
Give an example of a long-term change caused by weathering.
Sharp rock edges becoming smooth and rounded over time.
What is measured by the Mohr's scale?
Hardness
Ripples in sand are caused by...
wind