GEO113-Mineral and Rock Resources Lecture Notes
MINERAL AND ROCK RESOURCES. LECTURE NOTES . I. Introduction . Eight elements (O, Si, Al, Fe, Mg, Ca, Na, and K) make up 98% of the earth's crust. Many important elements are found, on average, in the crust in very small amounts (ppm ppb) Finding these elements in high concentrations is the exception and requires unusual geologic processes.