Bentonite is an aluminum silicate clay coming from volcanic ash that is classified as a smectite montmorillonite white clay. Bentonite can be sodium or calcium based (saponite and hectorite) with important differences in their physical properties. Sodium bentonite swells with the introduction of water to form a thixotropic gel.

About a third of the bentonite produced worldwide is mined from North and Central America, though there are producers in these 81 nations: Algeria, Argentina, Armenia, Australia, Azerbaijan, Belgium, Bolivia, Bosnia & Herzegovina, Brazil, Bulgaria, Canada, Chile, China, Colombia, Croatia, Cuba, Cyprus, Czech Republic, Denmark, Ecuador, Egypt, Ethiopia, Finland, France, Georgia, Germany, Greece, Guatemala, Hungary, India, Indonesia, Iran, Iraq, Israel, Italy, Japan, Kenya, Libya, Macedonia, Malaysia, Mexico, Moldova, Morocco, Mozambique, Myanmar, Namibia, Netherlands, New Zealand, Nicaragua, Nigeria, Norway, Pakistan, Peru, Philippines, Poland, Portugal, Romania, Russia, Saudi Arabia, Senegal, Singapore, Slovakia, Slovenia, South Africa, South Korea, Spain, Sweden, Tanzania, Thailand, Turkey Turkmenistan, Ukraine, UK, Uruguay, USA, Uzbekistan, Venezuela, Vietnam, Republic of Yemen, Yugoslav Federation, Zimbabwe.1

Bentonite has many industrial uses that take advantage of the: thixotropism, hygroscopic swelling, color, chemical content, refractory nature, plasticity, lubrication, etc. inherent in the mineral.

these uses include:

The world's major producer of bentonite at the time of this writing is American Colloid Co. who puts nearly 1.5 million tons per year on the market.

Bentonite toxicosis is a known health concern in people and cats who ingest bentonite clays. Myalgias, hypokalemia, severe anemia, lethargy, muscle weakness, dehydration and heart murmur appear to be symptoms associated with this condition. There is some opposition presented by cat litter companies to the notion that bentonite presents health risks.2


1. The Economics of Bentonite, 9th edition. (c)1999 Roskill. UK. 2. Suspected Bentonite Toxicosis in a Cat from Ingestion of Clay Cat Litter. Hornfeldt and Westfall. Minnesota.