Some time after its deposition, mineral veins were formed in the limestone.

In strip mining, huge machines tear away all the rock and earth above a mineral vein.

Adits are also used to explore for mineral veins.

Hushing is an ancient and historic mining method using a flood or torrent of water to reveal mineral veins.

The power sources were deep inside the hills, where natural mineral veins masked the readings.

The dominant trend for mineral veins of this stage is W-E.

"Lode" is a Cornish mining term for a mineral vein.

The slope of the walls, the patterns of the mineral veins, it was all different.

It is a fine "vertical" cave which is dry, deep, and mostly in big passage formed within a mineral vein.

The presence in the high part of the valley of mineral veins promoted since the antiquity an important mining activity.