Minerals

1. What physical property strongly distinguishes pyrite from chalcopyrite?

2. What two physical properties easily distinguish biotite from hornblende?

3. What physical property easily distinguishes quartz from fluorite? 

4. What nonmetallic mineral commonly displays striations on one of its cleavage planes?

5. Which one of the following minerals display an elongated crystal form:  

A) biotite  

B) augite

C) olivine

D) hornblende 

6. What is the key physical property (ies) that distinguishes the following green-colored minerals from   each other?

A) serpentine

B) chlorite

C) Olivine

7. List three minerals that can be scratched with your fingernail.

8. List two minerals that display cubic cleavage.

9. What mineral has a soapy to waxy, nonmetallic luster, a hardness of about four, and is greenish? 

10.  A) What mineral displays rhombic cleavage, and easily effervesces with dilute hydrochloric acid?

       B) What mineral displays rhombic cleavage, but does not easily effervesce with hydrochloric acid 

           (except when the mineral is powdered)?

11. Which one of the following minerals is mined for its zinc content?

A) sphalerite 

B) chalcopyrite

C) hematite

D) galena

12. List two minerals from the following list that can produce sulfuric acid (H2SO4) conditions in the natural   environment when they undergo chemical weathering? 

A) galena

B) magnetite 

C) muscovite

D) chalcopyrite

 

Igneous Rocks

1. Which of the following igneous rocks is a pyroclastic rock?

A) gabbro

B) scoria 

C) diorite 

D) tuff

2. Which of the following igneous rocks has the greatest percentage of mafic minerals (ferromagnesian)?

A) diorite 

B) syenite

C) gabbro

D) rhyolite

3. What is the major difference in the mineral composition of a syenite and a granite? 

4. What is the general pattern of change in mineral composition (mineral types and percentages) of                  

       phaneritic and aphanitic igneous rocks, trending from the light colored varieties to the darker varieties?

5. When an igneous rock has large crystals set in a finer-grained groundmass, the rock has what type of texture?

 

Sedimentary Rocks

1. A) A limestone derived from the consolidation of calcareous shells has what type of sedimentary texture?

    B) A quartz sandstone has what type of sedimentary texture?

    C) A limestone comprised of calcite crystals precipitated or crystallized from sea water has what type of          

               sedimentary texture?

2. If given a quartz sandstone that effervesces when a drop of dilute hydrochloric acid is added, what does this     tell you about the mineral composition of the rock sample?

3. What specific textural aspect of clastic sedimentary rocks is used to classify them? 

4. What key textural aspect distinguishes a breccia from a conglomerate?

5. What fine-grained sedimentary rock breaks along smooth planes (fissile)? 

6. Cross-bedding is an indicator of what type(s) of depositional environment(s)?

 

Metamorphic Rocks

1. list the names of four rocks that have a foliated texture.

2. List the names of two metamorphic rocks that have a nonfoliated texture.

3. Which of the following metamorphic rocks is or are commonly associated with contact metamorphism?

A) marble

B) gneiss

C) schist

D) quartzite 

4. What mineral (s) predominantly comprises the mineral composition of marble? 

5. The presence of garnet (an index mineral) in certain metamorphic rocks is a strong indicator of what grade of 

      regional metamorphism? 

 

Key to Questions

 

Minerals

1. Hardness

2. Hardness and cleavage

3. Hardness

4. Plagioclase

5. Hornblende

6. Serpentine - granular massive (no cleavage), hardness of four, soapy or waxy luster.

    Chlorite - cleavage in one direction on small flakes, to earthy masses, hardness of 2-2.5.

    Olivine - Hardness of 7, vitreous crystals.

7. Gypsum, Graphite, Biotite, others include: Muscovite and Chlorite.

8. Galena, Halite.

9. Serpentine.

10. A) Calcite

      B) Dolomite

11. Sphalerite.

12. Galena and Chalcopyrite. 

 

Igneous Rocks

1. Tuff.

2. Gabbro. 

3. Granite is quartz rich (> 20%)

    Syenite is quartz poor (< 5%)

4. There is a decrease in the percentage of quartz and potassium feldspar, whereas there is an increase in the percentage of plagioclase and ferromagnesians (e.g, hornblende, augite and olivine).

5. Prophyritic. 

 

Sedimentary Rocks

1. A) Bioclastic

    B) Clastic

    C) Inorganic Chemical

2. Indicates that the sandstone has a calcareous cementing agent.

3. Grain size.

4. Degree of grain roundness.

5. Shale.

6. Rivers/streams, coastal/beaches and deserts (associated with dunes).

 

Metamorphic Rocks

1. Slate, Phyllite, Schist, Gneiss. 

2. Quartzite, Marble, Others (hornfels, serpentinite).

3. Marble, Quartzite.

4. Calcite and/or Dolomite.

5. Medium grade metamorphism.

 

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