Smart Sand, Inc.
A maker of "Northern White" sand — a nearly pure quartz proppant used in hydraulic fracturing to hold open cracks in oil and gas wells — Smart Sand mines and processes it in Wisconsin and Illinois and ships it to well sites. Founded in 2011 and based in Yardley, Pennsylvania, the company was built to solve a supply-chain headache: getting high-quality frac sand to wellheads. The sand's name comes from where it's found — mined up north and naturally white because it's almost pure silica.