In our last article we discussed one of the common minerals found on the earth's surface. In this article the writer will attempt two things: first, to describe a few of the common rock-making minerals; and second, to discuss some of the simple ways of distinguishing the common igneous rock found on the earth's surface. The commonest igneous rock-making minerals, besides quartz, are the feldspars, the irons, pyroxene, hornblende, and the micas.
©1931 by Iowa State Teachers College
Cable, E. J.
Science Bulletin: Vol. 4:
4, Article 6.
Available at: https://scholarworks.uni.edu/science_bulletin/vol4/iss4/6