Selenite (mineral) was filled with mineral-rich water that drove the crystals' growth. The largest of those crystals weighs 55 tons, is long, and is over 500,000 years old. Gypsum occurs on every continent and is the most common of all the sulfate minerals. Gypsum is formed as an evaporative mineral, frequently found in alkaline lake muds, clay beds, evaporated seas, salt flats, salt springs, and caves. It is frequently found in conjunction with other minerals such as, copper ores, sulfur and sulfides, silver, iron ores, coal, calcite, dolomite, limestone, and opal. Gypsum has been dated to almost every geologic age since the
Interlanguage fossilization advance gradually until it becomes equivalent, or nearly equivalent, to the target language. However, during the second language learning process, an interlanguage may reach one or more temporary restricting phases when its development appears to be detained. A permanent cessation of progress toward the target language has been referred to as fossilization. This linguistic phenomenon, interlanguage fossilization, can occur despite all reasonable attempts at learning. Fossilization includes those items, rules, and sub-systems that second language learners tend to retain in their interlanguage, that is, all those aspects of interlanguage that become entrenched and permanent, and that the majority of second