Laboratory Manual for Introductory Geology 4e

APPENDIX 3.1
In these appendices, we present two ways of identifying or determining minerals. First, in Appendix 3.1, we provide flowcharts
for students who may be more visually oriented. Then, in Appendix 3.2, we present the same information in the
more standard determinative tables. Because both students and geologists think and work in different ways, we felt it was
important to provide both options. Use whichever works best for you!
Mineral Identification Flowcharts
A. Minerals with Metallic Luster
Magnetism Color Streak Hardness Breakage
Possible minerals
(see Appendix 3.3 for
additional properties)
Magnetic
Black or
dark gray
Black
Harder than a
glass plate
Magnetite
Copper
Copper
Harder than a
penny
Copper
Nonmagnetic
Gold,
brassy yellow
Black
Harder than a
penny
Chalcopyrite
Pyrite
Pyrrhotite*
Gray
Softer than glass,
harder than a penny
Three cleavage
directions at 90°
Galena
Silvery or
battleship gray
Reddish
brown
Softer than glass,
harder than a penny
May occur in
smooth mounds
Hematite*
(specular)
Gray-black
Softer than a
fingernail
One cleavage direction;
platy appearance
Graphite
Black
Harder than a
penny
Arsenopyrite
Brown
Yellowbrown
Harder than a
penny
Limonite
* Pyrrhotite and hematite are sometimes weakly magnetic.
APPENDIX 75