hyper, they initially had piques on the Canchete. These were holes up to 30 m verticle that the informales had dug to mine the veins with. At the 20m level, on one of these shafts/levels, a drift (tunnel) was dug horizontally to the east to exit the side of the hill. If I remember correctly that tunnel was around 40m long. Here is a photo to help you better understand what I am saying.