CHAPTER XXI 

 GOLD 



Gold Geologically an Obscure Metal 



What is gold? It is one of the so-called precious metals. 

 Why precious? Principally because it is not common, yet pos- 

 sesses qualities of great importance. For it men have traversed 

 the earth. The search for gold has lured mankind into unim- 

 aginable hazards. What is the source of gold? To say the pro- 

 found depths of the earth is not saying much, but is about all 

 that can be said. The struggle of men to find the precious 

 metal has been in a sense paralleled by the geologic stresses by 

 which the metal has emerged from the depths of the interior of 

 the earth. But for tremendous convulsions by which the crust 

 of the earth has been rent, upheaved and broken, rocks shattered 

 and fractures formed, probably man would never have known 

 the yellow metal other than as a chemical curiosity. Yet con- 

 trariwise as it may seem, gold is widely distributed throughout 

 the rocks of the earth, and is even present in solution in the 

 waters of the seas. Widespread though it is, yet because its 

 occurrence in commercially paying quantities is so rare, and its 

 behavior as one of the constituent minerals of the earth is so 

 obscure, and because it possesses properties that render it of 

 great practical value in the arts, it is ranked among the precious 

 metals. 



Gold is one of the elementary substances of which the earth 

 is composed. It is one of about 90 elements which make up 

 all the rocks, minerals, water and air of the earth. A wide range 

 of studies tends to show that gold occurs in all geologic for- 

 mations of all ages. The gold contained in the rocks of the 

 earth's crust is estimated to represent a value which would be 

 expressed in tenths of a cent per ton of rock. Shales are the 



