Gold mines are, as their name implies, a place where gold can be mined, but can refer specifically to an outcropping of rock where gold ore can be found and collected.
Warcraft: Orcs & HumansThis section concerns content exclusive to Warcraft: Orcs & Humans (aka Warcraft I).
King Llane has sent many a surveyor into the hills and mountains throughout the kingdom in search of new deposits of gold. You may discover one of these sites, and find that there are still veins of the precious metal to be mined. Peasants can be trained in the skills required to mine and deliver this gold to your Town Hall for disbursement as you see fit.
Some rock faces hold deposits of gold. You will recognize them because Blackhand has sent searchers out, and any that were located will have an entry way clearly marked. Peons will mine these holes and deliver the gold to your Town Hall for disbursement as you see fit.
Warcraft IIThis section concerns content exclusive to Warcraft II: Tides of Darkness.
Like in Warcraft: Orcs & Humans, gold is still used as a primary resource by both the Alliance and the Horde, and can only be mined by Alliance Peasants or Horde Peons.
Warcraft IIIThis section concerns content exclusive to Warcraft III.
The Gold Mine of Warcraft III is the same as the gold mines of previous Warcraft games: A node from where the Gold resource is collected. Peasants and Peons collect them in the same manner as the previous games, by traveling back and forth between the mine and a drop-off point. The Undead and Night Elf factions, however, can only collect them under specific conditions.
The Undead must first "haunt" a gold mine, once it is completed, up to five Acolytes can attach themselves around the mine to harvest the gold. The Haunted Gold Mine, like the Necropolis, does not require blight in order to be built.
The Night Elves must "entangle" a gold mine with vines. This is achieved by building or moving a Tree of Life next to a Gold Mine and, once at the site, it will automatically entangle the mine. Once it is finished, Wisps may attach themselves to the Entangled Gold Mine and begin harvesting.
Note: The Entanglement around the mine will disappear if the Tree of Life next to it is destroyed or moved away.
World of WarcraftThis section concerns content exclusive to World of Warcraft.
As World of Warcraft is based on the previous Warcraft games, gold mines make an appearance.
Gold mine subzones
Here is a list of subzones that are Gold Mines: