Question

If you specified a clay product (formed from decomposed volcanic ash, with a high content of the mineral montmorillonite), and this product has the capacity of absorbing a considerable amount of water, and swells accordingly, what building product would you be specifying?

Answer

The product is bentonite. It is used in roofing products and as an additive in brick making and concrete. It is also used in pet litter, as an animal feed additive (aids pellet binding), in oil, gas, and water drilling operations, and in waste water treatment.