00741cam a22002411 4500 gs 55000288 DLC 20260227111403.0 780821r1955uuuunmua 000 0 eng c gs 55000288 (OCoLC)4156871 U.S. Geol. Survey. Libr. TxEU OCoLC DLC premarc TN24.N6 A235 no. 32 Weber, Robert Harrison, 1919- Processing perlite, the technologic problems. Socorro, 1955. 3 p. illus. 28 cm. New Mexico. Bureau of Mines and Mineral Resources. Circular 32 Cover title. "Reprinted from Mining engineering, February 1955." Perlite. 28992 28992