Why is olivine a rare mineral in sandstone?

a. What is the range in grain size of sample 33 from the Athabasca University Rock Samples Kit? (Hint: Measure the size of the grains with a ruler.) How would you classify this rock, based on grain size?

b. What is the dominant grain composition? Give a rock name based on the discussion in Section 4 of Unit 4 in the Study Guide.

c. Describe the sorting and rounding of grains in this sample. Describe the source and origin of the sediment that makes up this rock.

Compare sample 33 with the volcanic breccia. Describe one way in which these rocks are similar. How would you determine their fundamentally different origin?