A major shareholder in U.S. Silica (SLCA -0.93%) is to sell 8.5 million shares of the company in an underwritten secondary public offering. Those shares will be offered at $22 apiece by a subsidiary of Golden Gate Capital, a financial investor in the materials firm. In addition to those 8.5 million shares, the seller has granted the issue's underwriters a 30-day option to buy an additional 1.275 million shares.

U.S. Silica currently has approximately 52.8 million shares outstanding.

The issue is expected to close on March 19. The company stressed that it will not receive any proceeds from the sale.

The joint book-running managers of the offering include Morgan StanleyBank of America unit Merrill Lynch, Jefferies, and Wells Fargo's Securities division.