How Are Opals Mined?
The Basic Process The simplest of opal mining operations can be performed by a single person. The miner digs a vertical shaft through layers of earth. Opal is usually found under a layer of hard sandstone. Once the miner has reached the layer of “potch,” the glassy, gray earth that may contain opals. The waste material is hauled out of the shaft with buckets as the miner drives horizontally, chasing the opal seam. If opals are found, they are removed with small mining tools due to their fragility. Taking it to the Next Level As with most everything, technology has been used as much as possible to increase success and productivity. Drilling machines using an auger bucket are generally used to create test shafts. Promising digs utilize tunneling machines with rotating cutting heads. Small front loaders and mechanized conveyors are used to remove overburden. The Largest Operations Open cut mining is used for large-scale operations. Large excavating equipment is used to remove the overburd
