Geology 300: Physical Geology
Geology 301: Physical Geology
Lab
Geology 305: Earth Science
Geology 306: Earth Science lab
Samples: Minerals, Sedimentary, Igneous, Metamorphic
Instructor: Arthur Reed, P.G.
Igneous
Rock Samples for Geol 301 Lab Activity 5.7
All
samples are approximately 1” – 3” in size
NOTE: ALWAYS CLICK ON THE SAMPLE NUMBER UNDER THE PHOTO TO GET
THE BEST/CORRECT VIEW OF THE MINERAL
This is similar to the intrusive igneous rock of our Sierra Nevada batholith (note the lack of the peach-colored mineral potassium feldspar).
SAMPLE 530b (also 530c)
SAMPLE 535b (also 535)
Very low specific gravity (less than 1)
Generally dark igneous rocks are higher in iron and magnesium, lower in silica, and higher in density.
This sample is an exception to that rule. Note the conchoidal fracture.