膨润土也叫斑脱岩或膨土岩。它最早发现于美国的怀俄明州的古地层中,为黄绿色的粘土;因加水后膨胀成糊状,后来人们就把这种性质的粘土,统称为膨润土。膨润土的主要矿物成分是蒙脱石,含量在85%～90%,另含少量长石、石英、贝得石、方解石及火山玻璃。可呈白色、含杂质时呈淡绿、 Bentonite is also called bentonite or bentonite. It was first discovered in the United States, Wyoming, the paleo-formations of yellow-green clay; due to the swelling into a paste after adding water, people later put this nature of clay, collectively referred to as bentonite. Bentonite main mineral composition is montmorillonite, content of 85% to 90%, and the other with a small amount of feldspar, quartz, beidellite, calcite and volcanic glass. May be white, pale green with impurities,