UNITED STATES MINERAL RESOURCES 



LIMESTONE AND DOLOMITE 



By Harold A. Hubbard and George E. Ericksen 



CONTENTS 



Abstract of conclusions 357 



Introduction 357 



Definitions 358 



Production, uses, and desirable properties 358 



Construction stone 359 



Portland cement 359 



Fluxes 360 



Lime 360 



Refractory dolomite 360 



Agricultural limestone 360 



Other uses 360 



Geologic environments 360 



Distribution and resources 361 



Problems for research 363 



Selected references 363 



FIGURE 



43. 



Graph showing production and use of limestone 

 and dolomite in the United States, 1950-69__ 



TABLES 



359 



69. Principal sources and some potential sources of 



high-calcium limestone in the United States- 362 



70. Principal sources and some potential sources of 



high-purity dolomite in the United States 363 



ABSTRACT OF CONCLUSIONS 



Limestone and dolomite are at or near the earth's surface 

 over at least 10 percent of the continental areas, and the 

 resources are extremely large. However, high-purity stone 

 suitable for chemical and metallurgical use is restricted in 

 extent, but its resources are large, also. For uses in which 

 physical properties of the rock are important, as in con- 

 struction, many kinds of rock can be substituted for lime- 



stone and dolomite. For uses in which the chemical proper- 

 ties are important, substitutes are few, generally scarce, 

 and more costly. Because limestone and dolomite are abun- 

 dant, the price at the mine is low, and shipping costs con- 

 stitute a major part of the price to the consumer. About 

 two-thirds of the limestone and dolomite mined in the 

 United States is used because of its physical properties, 

 chiefly in construction as aggregate and fill and for re- 

 lated purposes, but a small amount is also used as an in- 

 dustrial filler. The remainder is used because of its chemical 

 properties as a raw material in the production of Portland 

 cement, lime, alkali, calcium carbide, and glass; for flux in 

 metallurgy; for agricultural purposes; and for a large 

 number of minor purposes. 



The largest resources of high-purity limestone and dolo- 

 mite in the United States are in the central and eastern 

 parts of the country, but details of the distribution of such 

 stone are incompletely known. Consequently, some potentially 

 valuable deposits are endangered by urban spread and by 

 zoning regulations that restrict or prevent quarrying in 

 populous areas. 



INTRODUCTION 



Limestone and dolomite, commonly referred to as 

 carbonate rocks, are among the world's most widely 

 used mineral commodities and are essential to mod- 

 ern industrial society. Huge quantities of these rocks 

 are consumed annually in construction, in agricul- 

 ture, and by the chemical and metallurgical indus- 

 tries. The total value of limestone and dolomite ex- 

 tracted annually is exceeded by that of only a few 

 mineral commodities — sand and gravel, petroleum, 

 and coal. Limestone and dolomite used for their 

 physical properties, chiefly for construction pur- 

 poses, occur in extremely large quantities on all the 

 continents and constitute at least 10 percent of the 

 near-surface rock of the continents. Large quanti- 

 ties of limestone are used in the manufacture of 

 cement; the rock suitable for this purpose may be 

 rather impure but is widespread and abundant, 

 though less so than the limestone used in construc- 

 tion. High-calcium limestone and high-purity dolo- 

 mite, which are needed for chemical and metallurgi- 

 cal purposes, are much less widespread and abun- 



U.S. GEOL. SURVEY PROF. PAPER 820 



357 



