"....the dominant share of the bentonite we extract is processed into the form of final products in Slovakia"
"bentonite is an ecological raw material, important and necessary for several branches of industry, environmental protection and human use"
"several hundred jobs are directly linked with the extraction of bentonite directly in the region of Žiar nad Hronom and its surroundings"
"the extraction and use of raw minerals can also be done in an ecologically acceptable and long-term sustainable way"
"REGOS s.r.o., is the only company in Slovakia that mines bentonite on the basis of a complex environmental impact assessment of the mining activities and in conformity with conditions approved in final decision of the Slovak Ministry of Environment"
"We began to assess the impact of bentonite mining on the environment voluntarily, because we are responsible towards nature and the interests of residents of the region"
"the mineral wealth of a country and its sustainable use is in the interest of all citizens of Slovakia and its development"
Bentonite is a clayey mineral that originates by the transformation of volcanic glass and ash in an alkaline, most often an oceanic or lake environment, with the origin of clay-like minerals from the smectite group (mainly montmorillonite, beidellite and nontronite).
The first to use the term bentonite was W.C. Knight, in 1887, who named bentonite after the town of Fort Benton in the American state of Montana.
Bentonite is a clayey material of earthy structure, usually white, grey up to light-green in colour. Upon freshly cutting it, it has a waxy shine.
It is these special properties of smectite minerals in bentonite that give it an exceptional standing among other clays in terms of its uses. The swelling of bentonites upon contact with liquids, which can reach up to 12-fold growth of their volume, but also other properties is especially important. Physically and chemically bentonite fixes a whole line of substances and is used for their selection sorption, or separation. Another of its important properties is its viscosity, resulting from its huge internal surface (up to 900 m2/g), given by the large number of interstitial spaces (a large reaction surface) and, of course, by the many crystals in a volume unit. A typical property of bentonite is the high capability for base exchange, i.e. the ability to accept certain cations from a solution and substitute them for free Mg, Ca, or alkali. The significant rheological, sorption and colloidal properties of bentonites, or their combination, predetermines them for broad-spectrum use not only in industry but also in human areas (pharmacy, the food industry, cosmetics), environmental protection, etc.
The oldest and largest deposit of bentonite in Slovakia is in Stará Kremnička, the Jelšový potok (stream) location. Quarrying has been done here since 1974. At present, together with the deposits in Kopernica and Lutila, they form the most significant deposits in all of Slovakia. Smaller deposits are found in Bartošova Lehôtka, Dolná Ves, in Hliník n/Hronom, Zvolenská Slatina, Lieskovec and in eastern Slovakia, e.g. Fintice, Lastovce, Michaľany and the like. All domestic bentonites are practically Ca, or Ca-Mg bentonites and are predominately formed of the mineral montmorillonite. Bentonites are quarried via surface mining.
Bentonite is first of all an ecological natural raw material, which has irreplaceable and broad-spectrum uses in society: