1
The stone test wall was constructed to study the performance of stone subjected to weathering. It contains 2352 individual samples of stone, of which 2032 are domestic stone from 47 states, and 320 are stones from 16 foreign countries. Over 30 distinct types of stones are represented, some of which...
Grade Level   9 10 11 12
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2
Sinkholes are natural depressions in the land caused when limestone and soils dissolve. They form when groundwater removes rock underground. They can form by slow gradual sinking or by sudden collapse of an underlying hole. Sinkholes are common in about one quarter of the U.S. You can usually...
Grade Level   6 7 8 9 10
Classroom Activities Curricula and Instruction
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