mining vs salt-working

mining and salt-working both are nouns.

Word	Noun	Adjective	Verb	Adverb
mining	Yes	No	No	No
salt-working	Yes	No	No	No

As nouns, salt-working is a hyponym of mining; that is, salt-working is a word with a more specific, narrower meaning than mining:

Other hyponyms of mining include placer mining, opencast mining, strip mining, fracking, salt working.

mining (noun)	salt-working (noun)
the act of extracting ores or coal etc from the earth	The manufacture of salt.
laying explosive mines in concealed places to destroy enemy personnel and equipment