A form of luminous energy emitted when certain minerals are irradiated with ultraviolet light. The way in which a rock or mineral breaks. Minerals with a specific gravity greater than 2.87. An emission of light due to a stimulus like directed pressure, heating, rubbing, irradiation with X-rays, ultraviolet light, etc. The manner in which light is reflected from a rock or mineral's surface.
Native elements are uncombined with other elements.
Native metals are found as minerals, such as gold, silver and copper. A mineral with a compact mass and slender branching crystals similar to feathers. This structure is common to some sulphosalt minerals. An instrument for measuring the specific gravity of a mineral or rock. Minerals formed by change at the loss of pre-existing minerals.