A mineral was a naturally occurring substance that was solid, inorganic and had an ordered atomic structure. They were studied by mineralogists, (TV: The Sensorites) and were often the cause of colonisation (TV: Colony in Space) or wars. (TV: The Daleks' Master Plan, The Curse of Peladon et al.) Mineral surveys were sent to detect the presence of minerals. (TV: Colony in Space, Kill the Moon)
Some minerals, such as quartz (TV: Marco Polo) and duralinium, were mined from naturally occurring veins of ore. (TV: Colony in Space) Others, such as zelanite, keefan, and lucanol, had to be extracted using specialised equipment, such as Kaldor sandminers. (TV: The Robots of Death)
Minerals could be purposed in a variety of ways. Some functioned as power sources, such as bernalium or genellium. (TV: The Wheel in Space, AUDIO: The Invasion of E-Space)
Some minerals, like duralinium, were used in construction. (TV: The Monster of Peladon) They could be components, as jethrik was for certain types of warp drive engines, (TV: The Ribos Operation) taranium was for some time travel devices, (TV: The Daleks' Master Plan et al) and zeiton crystals were for TARDISes. (TV: Vengeance on Varos, Time Crash) Similarly, mineral nitrate was used to produce the insecticide DN6, (TV: Planet of Giants) and the Fourth Doctor described automated systems as being made of "minerals and circuitry". (TV: The Armageddon Factor)
Several types of minerals affected psychic powers. Metebelis crystals could break hypnotic spells, enhance intelligence and enhance psychic powers. (TV: The Green Death) The vibrations of refined voolium and madranite one-five crystals could be used to power a psychic interference transmitter to neutralise psychic powers. (TV: The Pirate Planet)
Some minerals were hazardous, such as vastial, which would become unstable and combust at temperatures above ten degrees, (TV: Attack of the Cybermen) or vionesium, which reacted rapidly and violently with oxygen. (TV: Terror of the Vervoids) Others were protective in nature; the fluon radiation produced by Metebelis crystals (PROSE: Return of the Spiders) could be blocked by minerals also found on Metebelis III. (TV: Planet of the Spiders)
Still others had stranger effects. Cerulium (found on Ceres) had the property of inhibiting free will, (TV: Sirens of Ceres) and radioactive thaesium was used by Solonians to cause the "mutations" that were part of their life cycle. (TV: The Mutants)
Human bones contained calcium minerals, which could be used as fertiliser. (TV: Smile)
Other minerals included galdrium and assetenite four-five-five. (TV: The Pirate Planet)
Dark planets could support life, despite the lack of adequate light, as radioactive minerals were present. (PROSE: The Dark Planet)
Proamonium, only found on Proamon, was the rarest mineral in N-Space, (PROSE: Night of the Humans) although another account suggested that the rarest mineral in the universe was taranium. (TV: The Daleks' Master Plan) Argonite was the most expensive mineral in Earth's galaxy. (TV: The Space Pirates)
Animal, Vegetable, Mineral? was a successful panel game for archaeology experts that ran on British television from 1952 to 1959. (PROSE: The Time Traveller's Almanac)