Heterogeneous 3 : A substance that consists of more than one phase and is not uniform, such as colloids, emulsions, etc. It has different properties in different parts. (Bul D11)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}