South Crofty Mine Underground 13: This page is continuing the images of drive development. This mainly covers the use and priming of the explosives before the blasting of the face.
South Crofty Mine Underground 13.1 – A wide view of the drive face, it gives a good idea of how many holes needed to be drilled for a round of blasting. The plastic tub in the foreground was the container from where the explosive was forced into the holes using compressed air.
A few lines from Nick Le Boutillier about blasting in South Crofty.
Powergel was a plastic explosive that came in foot-long 3/4 inch plastic-wrapped ‘sausages’. This was used at the end of drill holes to break out to the hole sockets. Also by moonlighting geologists as ‘slap dab’ to ‘blow shit up’, which was enormous fun.
South Crofty Mine Underground 13.2 – Vivian Mugford on the right of the image. The drive was very wet here with water pouring from the roof. I do not know the location of these images, if anyone does please let me know.
The main explosive in use was anfo, which is ammonium nitrate mixed with diesel oil. This was pink and had the consistency and form of small polystyrene balls. It was blown by compressed air into the drill holes, the detonators were placed in the Powergel and the wires run out of the holes. Also these were sometimes tamped by a bit of clay to close the hole.
South Crofty Mine Underground 13.3 – A close up of the box of explosives. When working South Crofty was one of the biggest users of explosives in the country.
Trammers would sometimes use Coretex, which was a nitrate-based explosive that looked like white electrical cable. This could be wrapped around troublesome rocks and was very effective. However it was not popular, because chemicals from the explosive were readily absorbed by the skin and could easily lead to very severe blinding headaches and nausea.
South Crofty Mine Underground 13.4 – My favorite image on this page Vivian Mugford using a tamping bar to force the Powergel explosive into the drilled holes. In the early days of Cornish Mining this was a dangerous job and many miners suffered from horrific injuries when the charges exploded.
South Crofty Mine Underground 13.5 – Vivian Mugford Underground Miner priming the charged holes in preparation for blasting.
South Crofty Mine Underground 13.6 – Another image of the end, the many fuses can be clearly seen hanging from the drilled holes.
South Crofty Mine Underground 13.7 – Water was pouring from the roof. That and the heat made the humidity unbearable in such a confined space.
South Crofty Mine Underground 13.8 – A final image of Adrain. He is charging the lowest hole of the set which was known as a “lifter”.
On another day, the next two images are again of Adrian Mugford in another part of the mine. Once again drilling for the next blast. Present day Health and Safety laws restrict the use of these rock drills because of the extreme vibration the operative felt.
South Crofty Mine Underground 13.9 – This was possibly located in a sub level. To the right of the miner was a large hole in the ground leading to the level below.
South Crofty Mine Underground 13.10 – Another closer image of Adrian Mugford drilling a face in preparation for the next blasting.
South Crofty Mine Underground 13.11 – Another day and another drive. John Ursoro Mine Geologist watching the drive being primed with explosives. I have no detail on location, I also like this set the lighting is very effective.
South Crofty Mine Underground 13.12 – Underground miner Brian Whittaker with a new batch of fuses for priming the detonators.
South Crofty Mine 13.13 – Another box of Powergel being opened.
South Crofty Mine 13.14 – The container in front of the face was used to force the anfo explosive into the drilled holes.
South Crofty Mine 13.15 – Each hole had Powergel explosive in the top. The fuse was subsequently placed into this.
South Crofty Mine 13.16 – It’s amazing how other miners would appear. Then watch with interest.
South Crofty Mine 13.17 – The whole face of the drive is covered with mineral structure.
South Crofty Mine 13.18 – A final image in this group, the face has been heavily drilled and primed. It is now nearly ready for firing.
The rest of the images on this page were taken on the NPZ (North Pool Zones) crosscut on 400 Fathom Level South Crofty Mine. This was on a day with Nick Le Boutillier. This set clearly shows the ANFO explosive being blown into the drilled holes by compressed air.
South Crofty Mine 13.19 – Here Paul Gallie along with another South Crofty Miner are charging the holes with the explosives. This is the only image I have of the anfo, which is Ammonium Nitrate mixed with diesel oil being forced into the holes.
South Crofty Mine 13.20 – Nick Le Boutillier Senior Mine Geologist is standing behind the two miners, he is examining the lode at the end. This was also an important task for the Geologists who closely monitored progress and also took regular samples.
South Crofty Mine 13.21 – Nick Le Boutillier sampling the face. The rails had been laid by the miners to enable the rocker shovel to get to the end of the drive.
South Crofty Mine 13.22 – Probably a brief discussion on the progress of the days work.
South Crofty Mine 13.23 – A final image of the drive. I particularly like this one due to the framing of the rails also the low angle of the camera.
South Crofty Mine Underground 14