In order to access the precious material laying hidden underground, miners would drill and blast rock faces to get behind it. The Hutchings Museum has a large collection of drilling and blasting artifacts used in this process.
Drill Bits
To access precious ore hid deeper in the rock, miners would use diamond drills to drill holes into the rock face. Early on, single and double jacks were used to pound, by hand, the drill into the rock face about three to four feet.
Once miners had drilled a hole into the rock face, they would clear out the debris and place dynamite in the hole. The fuse would be lit, the blast would go off, and miners would clean the dust and debris that settled. The process would repeat as they drilled further into the rock.
As pneumatic (air) and water powered drills came around, miners could drill eight to ten feet into the rock face. This required a longer scoop to clean debris so they could place the dynamite in and blast the rock.
Holes were drilled into the face about a foot apart. There would be about 12 holes before they would place the dynamite and blast the wall.
Drilling and blasting created a great deal of dust that would get blown around and breathed in by the miners. Many miners suffered from silicosis and black lung because of the dust and soot they were constantly breathing in. As water powered drills came along, the drills would spray water through a hole in the drill bit. This created a slurry of mud, but was significantly better for the miners health.
This Liddicoat drill bit box would have held a small drill bit.
Drill bits usually have a hollow core. As they pulled out the hollow core, a cylinder of the rock came out with it and provided a sample of the rock they were drilling.
Drill Cores
The hollow opening of the drill bits extracted a cylinder of rock as the bit was pulled out. Miners would label the cores, box them, and take them to a geologist to be analyzed. This core is comprised of galena.
This drill core is also partially comprised of galena. Galena is lead that has not been processed and is safe to have and handle.
A geologist would analyze the drill core samples to see if the ore was worth mining. This drill core features open pockets from crystals.
Iron pyrite, commonly known as "fool's gold," resembles real gold due to the metallic gold color. The cubic structure of pyrite and other properties differentiate the two materials. This drill core showcases beautiful pyrite veins.
Pyrite, quartz, and calcite were not mined for their intrinsic value, but if miner's encountered samples containing those specimen, they knew they were drilling in the correct direction. This core has a sample of pyrite inside.
Blasting Caps
Blasting caps worked as detonators. They contain a small charge that, when ignited, set off a larger explosive. Blasting caps, in turn, would set off the sticks of dynamite that were placed in the drill holes.
The purpose of blasting caps was to improve safety for the miners. Dynamite and other explosives were able to have a higher activation energy (energy required to start the reaction) so as to protect against accidental drops that would set the blast off. They also helped to regulate the timing of the explosion and allow time for the miners to leave the area. Black powder fuses are difficult to control, so using blasting caps was a safer way to blast rock.
Although blasting caps tried to help improve the safety of miners, they also proved to be quite dangerous. The cap ends needed to be crimped, but if they were crimped too close to the explosives inside, it would ignite. Miners would often crimp caps with their teeth, presenting the same problem. If they crimped in the wrong spot, they were at risk for an explosion in the mouth and face.
Respirator
The dust and soot that is kicked up while drilling and blasting was extremely harmful for the health of miners. "Black lung" for coal miners and silicosis for others were very common illnesses that miners suffered from. When miners could no longer work, many went to nursing homes where the eventually died of asphyxiation. Unions pushed heavily for required filters. Even once water powered drills came along, filters were still worn as an extra precaution.
