Five companies are authorised to operate mines in Ireland:
Boliden Tara Mines (lead zinc mine, Co Meath)
https://www.boliden.com/operations/mines/boliden-tara
https://goo.gl/maps/HeSKkkL4q9b4kTkw9

Marble mines, Co Galway
Joyce’s Marble Quarries Ltd. / Connemara Marble Products Ltd.
Barnanoraun (part), County Galway
Tievebreen (part), County Galway
Cregg (part), Ballinahinch, County Galway
53.46786996142937, -9.727224509914068

Fireclay / Coal mine, Co Laois
Fleming’s Fireclays Ltd.
Moyadd (part), Aghadreen (part), Knockacrin (part) and Slatt Lower, County Laois

Gypsum mine, Co Monaghan
Gyproc, formerly known as Gypsum Industries
Gypsum, anhydrite and all other minerals

426 prospecting licenses are held by 43 companies
A Prospecting Licence typically covers some 35 square kilometers. There are currently over 2,000 delineated Licence Areas covering the whole country, which are defined by townland boundaries.
A searchable online map, with current licence holder information for all the Prospecting Licence Areas (PLA) and the composite townlands:
https://www.gov.ie/en/service/306e8-view-mineral-exploration-and-mining-maps-reports-and-data/
Minerals Prospecting Licences Granted – The licensed minerals are abbreviated as follows:
Base metals (Bm); Barytes (b); Gold, Ores of (g); Silver, Ores of (s); Platinum Group Elements, Ores of (PGE), Rare Earth Elements, Ores of (REE); Molybdenum, Ores of (Mo); Beryllium, Ores of (Be); Caesium, Ores of (Cs); Lithium, Ores of (Li); Niobium, Ores of (Nb); Rubidium, Ores of (Rb); Tantalum, Ores of (Ta); Tin, Ores of (Sn); Tungsten, Ores of (W); Manganese, Ores of (Mn); Cobalt, Ores of (Co); Iron, Ores of (Fe)
List of prospecting licenses: