THE ELEMENTS OF ECONOMIC 
GEOLOGY 
PART 1 
INTRODUCTION 
CHAPTER 1 
THE SCOPE OF ECONOMIC GEOLOGY, AND THE 
SEARCH FOR ORES 
Economic Geology applies the principles of geology to the 
study of the useful materials in the earth’s crust, and to the 
investigation of their origin and distribution so as to help 
mining to its ideal—the working of minerals at the least cost 
and with the greatest profit. How effective geology may ‘be 
is shown by the statement by J. E. Pogue in his Economics 
of Petroleum (1921, p. 343) that of an extensive series of 
American oil-well records, 85 per cent. of the wells sunk in 
accordance with geological advice proved successful, whereas 
of those sunk at random, only 5 per cent. were productive. 
The chief minerals with which the economic geologist has to 
deal are building stones, slates, and marbles; the materials 
used for cements, the clays for pottery and bricks, and sands 
for glass manufacture and moulding ; the mineral fuels, 
including coal, mineral oil, and peat; the mineral bitumens ; 
the minerals used as fertilizers, including phosphates, nitrates, 
potash, and lime; various minerals of service from special 
physical and optical qualities, such as micas and gems ; 
the sodium and potassium salts; the ores which furnish 
the metals indispensable to a civilized community. and