A caged bird kept caged in mines because its demise provided a warning of dangerous levels of toxic gases.

plural of miner's canary

plural of mineral water

One who carries out data mining.

plural of accessory mineral

plural of mineral oil

white spirit

(mining) Carpeting in sluice boxes used to collect heavy minerals from sluiced paydirt.

plural of mineral lick

A block of salt enriched with minerals, licked by herd animals to supplement their diet. / A natural source of such minerals licked by wild animals.