Why do some minerals exist in more than one color?
What will be an ideal response?
Element substitutions. Examples: purple quartz contains iron substituting for silicon, pink quartz contains titanium substituting for silicon, dark blue, green, or brown calcite contain iron substituting for calcium, pale purple to deep red calcite contains manganese substituting for calcium.
Impurities without element substitution. Examples: milky quartz has water droplet impurities.
Radiation damage: black smoky quartz.
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Which location on this figure from the Investigation is located on a divergent plate boundary?
A) 1
B) 2
C) 3
D) 4
E) 5
Which section of the Earth has the highest material density?
a. crust b. mantle c. asthenosphere d. outer core e. inner core
Which of the following describes the mineral processing technique whereby a chemical solution percolates through crushed ore and liberates the desired elements?
A. ionization B. hydration C. smelting D. dredging E. leaching
Marine geologists can predict the age of igneous rocks of the sea floor by measuring ________.
A. the velocity of earthquake waves B. magnetic anomalies C. their grain size D. the percent of iron-rich minerals in the rock E. their density