Chapter 26 



FOUNDRY SANDS 



H. Ries 



Emeritus Professor of Geology 

 Cornell University 

 Ithaca, New York 



The term foundry sand is applied to those sands which are used for 

 making the molds and cores in which metals are cast. The molds form 

 the outside of the casting, and the cores make the hollows in it. 



These materials are of considerable economic importance. In 1947 

 the tonnage produced in the United States amounted to 8,308,434 

 short tons valued at $11,944,228. In addition to this, some sands were 

 imported. Michigan, New Jersey, Illinois, Ohio, and New York were 

 the leading producers. 



Foundry sands are widely distributed in the United States, but only 

 special types of sands are suitable for this purpose, because the sands 

 have to meet rigid requirements of permeability, strength, and volume 

 change with temperature. For a more detailed discussion of foundry 

 sands than given in this chapter, see Ries (1948). 



The predominating mineral in most foundry sands is quartz, and 

 next to it in abundance is feldspar. In most foundry sands the feldspar 

 content is relatively low, particularly in sands used for casting steel. 

 Some of the glacial outwash sands of central New York contain ap- 

 preciable amounts of feldspar. The sands of the Bridgeton and Pen- 

 sauken formations of New Jersey contain as much as 15 percent. In 

 California most of the soft Eocene and Miocene sands are strongly 

 feldspathic, as are also the dune sands on Monterey Bay, California. 

 Sands containing as much as 30 percent feldspar have been used in 

 Illinois. 



Mica is present in small amounts in some foundry sands, but 

 highly micaceous sands are not used. Many sands contain small 

 amounts of dark minerals such as zircon, ilmenite, rutile, and mag- 

 netite. Some sands contain minor amounts of leucoxene, staurolite, 

 kyanite, tourmaline, and garnet. 



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