clothes conveyor system The simplest form of opal mining is by shaft sinking with a pick and shovel. A shaft is sunk reduce until some promising "opal dirt" is discovered. Length of the shaft could be as short as three metres or as long as 20 metres. A handpick or screwdriver must be used to extract any opal found, because of the frailty of the stone. Health...
2 mesiUomini in cerca di Donne2669 - 30 Faunce Crescent11 visualizzazioni