Cleavage occurs when a mineral breaks along planes of weakness. These weaknesses are a part of the mineral's crystalline structure. Cleavage may occur in one, two, three or all directions. More » Science Earth Science Geology

More than 4,000 minerals are officially recognized, and up to 100 new ones are described yearly. Minerals are rocks or sand that have more than one element in their structure. Quartz, for example, is a mineral composed o... More »

Sports that involve running, such as basketball and soccer, can increase the risk of stress fractures in the foot and ankle, according to the American Academy of Orthopaedic Surgeons. In addition, gymnastics, ballet and ... More » Health Conditions & Diseases Wounds & Bruises

According to Brooklyn College, cleavage occurs when a rock breaks along smooth planes that are parallel to areas in which the mineral has weak bonds. By contrast, rocks are said to fracture if they break irregularly, bec... More »

Several methods exist to identify minerals, including the streak test, the Mohs hardness scale, the fracture test and the acid test. Based on these tests and the mineral's physical appearance, scientists can identify wha... More » Science Earth Science Geology

Some important characteristics of minerals are color, hardness, streak, cleavage, fracture and luster. These characteristics do not require any complicated equipment to determine and are useful in identifying specific mi... More »

Quartz is a mineral, while granite is a rock made up of minerals. Only one of those minerals is quartz. Pure quartz is silicon dioxide and is hard and transparent, but impurities can give it a range of colors. More » Science Earth Science Geology