Activators in Fluorescent Minerals

摘要: Why does calcite from Franklin, New Jersey, fluoresce red, elsewhere white, green, or blue, while many other calcites do not at all? In most cases, the fluorescence is caused by presence in mineral of an “activator.” An activator usually thought as a “foreign” element, sometimes present only small amounts. When fluoresce, it may be because contain suitable activator. Of somewhat more than 90 elements which occur nature, few appear to important activators minerals. These include manganese, uranium, some “rare earth” metals, and others.