central heating - a heating system in which air or water is heated at a central furnace and sent through the building via vents or pipes and radiators
exists and is an alternate of . Five physical characteristics of a mineral are: hardness, luster, diaphaneity, colour, and streak.
A mineral species has to possess these five characteristics... Minerals are solid, naturally occurring, inorganic compounds that possess an orderly internal structure and a regular chemical composition. A mineral species has to possess these five characteristics to be regarded as scientifically valid. The first and most basic characteristic of all minerals is that they occur naturally.