Mineral (3)
'mineral' is the definition.
(ore is a kind of mineral)
This is all the clue.
(Other definitions for ore that I've seen before include "Small coins" , "foreign money" , "Mineral-bearing rock" , "Danish currency" , "Mineral - Scandinavian monetary unit" .)
'mineral' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for opal that I've seen before include "Milky white gemstone" , "precious jewel" , "Mineral used as a gemstone, of hydrated silica" , "Type of gem" , "Milky white gem" .)
(Other definitions for beryl that I've seen before include "Girl's name - precious stone" , "Girl's name - jewel" , "Gem, fem. name" , "Pale greenish" , "Gemstone (for Ms Bainbridge?)" .)
'mineral' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for inorganic that I've seen before include "Non-carbon (chemistry)" , "Man-made" , "without carbon" , "What can describe something alien to life" , "Not derived from living matter" .)