The term "fracking sand" refers to sand and similar small materials that serve as “proppants” -- which are blasted under pressure into a shale gas well along with large quantities of water and industrial fluids to stimulate gas production. Proppants are used to “prop” open the underground cracks from which natural gas is harvested during hydraulic fracturing.
Typical proppants include actual sand crystals (such as from quartz/silica or sandstone), sand that has been industrially coated with resin (called resin-enhanced sand), ceramic crystals, or other suitable materials.
Industry publications estimate that each shale gas well requires approximately 5 million pounds of sand or other proppant for the hydraulic fracturing process. The quantity of proppant can vary from as low as 2.5 million pounds to up to about 7 million pounds, depending on specific geological variations and characteristics of a shale formation.