4. A proppant is a material that is mixed with water and chemicals and pumped into an oil or gas well as a part of the hydro-fracking process. The function of the proppant is to “prop” open the cracks in the rock that the fracking process blast and pressure create so that the oil and/or gas can continue to flow out. Wisconsin sand is the best fracking proppant that the industry has discovered to date (as of the end of 2013). The oil and gas industry is working very hard to develop a synthetic proppant (for example, a ceramic) that could be created at the well site) to minimize transportation cost. After all, sand is heavy and Wisconsin is a long way from Montana!