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Gold is known as a noble metal in that it will never rust, and is not affected by most acids and chemicals. It can however be dissolved by a mixture of hydrochloric and nitric acid known as aqua regia(Latin royal water), or by sodium cyanide, or by acetic acid mixed with certain oxidants.

From time immemorial gold has been the desire of those aspiring to riches, or to make sacred or venerable objects. Examples are the Israelites in the Bible worshipping a golden calf when Moses came down from Mount Sinai, and Jason and his Argonauts searching for the Golden Fleece.

An Irish prospector Paddy Hannan discovered gold in Kalgoorlie in 1893, which led to the discovery of the Golden Mile which was the richest deposit of gold in the world.

paddy hannan

Gold is an igneous extrusion from the boiling interior of the earth, billions of years old. It is generally found as lumps of native gold at times contained in ore known as gold tellurides, which are compounds of tellurium and gold. The Golden Mile contains such gold deposits among others.

Ore sample

One of the largest nuggetsof free gold ever found was the Golden Eagle,discovered in the Kalgoorlie area in 1931in a hole in the road, by a 17-year-old lad Jim Larcombe.

Golden Eagle

Golden Eagle Finder

The Golden Mile today is mined by a huge open cut excavation known as the Super Pit where the ore is mined by drilling and blasting, followed by loading of huge tip trucks by equally huge excavators for transport to the treatment plant for extraction of the gold. When I was lad things were not so simple.

In those days, the ore was mined by the old established method of shaft mining, which was far more expensive, onerous, time-consuming, dangerous and far less efficient than open-cut mining. Over the years, the Golden Mile had over 100 operating mine shafts, distinguishable by their headframes, sunk to depths of up to 3,600 feet (1000 metres). Many of those left have been devoured by the Super Pit commenced in 1992, which is now in excess of 4 kilometres by 1.5 kilometres in plan view, and 620 metres in depth. There are now no vertical shaft mines operating in Kalgoorlie.

Super Pit

In the late 1950s while on a long vacation from university, I obtained a job as a sampler on the Lake View and Star gold mine in Kalgoorlie. The shaft mining operation comprised two main sections, the mine itself for extracting the gold-bearing ore, and the treatment plant for extracting the gold from the ore.

The treatment plants on all shaft mines were extremely involved, including such things as ore crushers, ball mills, cyclones, vibrating screens, revolving filters, thickener tanks (filled with sodium cyanide solution) and gold smelters, which delivered the final product – gold bars

treatment plant

goldfly1921

There was also an Assay Office which analysed the amount of gold in a sample so that the mine geologists could plan ahead, and direct the mine surveyors who set out the underground excavation.

The Lake View and Star mine shaft itself was dominated by a huge steelhead frame supporting two huge sheaves at the top, which in turn supported a steel cable running from a mechanically driven friction winch winder on the surface, to the two cages or skips simultaneously being lowered and raised in the shaft below. Both were connected with a tail cable to give continuity of movement. The cage was for men and gear, and the skip was for ore. The winder driver communicated with those below ground with electric bells, and nothing more.

 

friction winch

The shaft, which was in excess of 2,000 feet deep, had landings called plats at every 100 feet. From these plats, horizontal tunnels called drives were drilled and blasted for great distances in excess of a half mile into the ore body. The drives had rail tracks laid, so that wheeled steel trolleys could be filled with ore, and pulled by small electric locomotives to the plat for loading into a skip for hoisting to the surface.

undergminfl921 

The ore between levels was mined by sloping excavations called stopes. The rock was drilled and blasted, and the ore then loaded into the trolleys below. My job as a sampler entailed climbing up the slope and chiselling ore across the face, so that it could be assayed for gold content. On my first day, I was issued with a miner’s helmet with a light powered by an acid battery to attach to my belt. I was taken down in the cage, shown around and that was it. No safety induction whatsoever. Such things did not exist. I was not told that there were specific times for blasting or even how it worked.

Using drills powered by compressed air and diamond-tipped drilling rods, the miners called machine miners would drill holes about eight feet deep at one-foot centres into the rock face. They would then load the holes with sticks of explosive called gelignite, fitted with electrically activated detonators attached to wires leading to the detonating device. There were no masks - everyone continually breathed in silica dust, and most machine miners met an early end because of silicosis.

Miners drilling

One my first day,I laboriously climbed up a stope to sample the face and was confronted with a rock face filled with holes and protruding coloured electrical wires. The penny finally dropped and I scrambled over the rocks down the stope and raced out onto the plat - then Kaboom from the stope as the face exploded.

There were small vertical shafts between the horizontal drives called wines which were used for access between levels. It was common for the miners to drill and blast new winzes from the bottom up, which was called raising, and consisted of progressively drilling and blasting the roof. No one told me. One day I walked along a drive beneath a winze under construction. When I returned not long after, there was a great slab of rock weighing tons on the drive directly under the winze, which would have crushed me.

Mining Layout

 In the main shaft, the cage for men/gear was counterbalanced with the huge deep skip for transporting the ore to the surface. It was forbidden to ride in the cage with gear, and the cage and the ore skip never stopped at any of the levels at the same time. Wanting to get to another level while the winder was hauling ore in the skip, I pulled the cord on the plat signalling the winder driver to stop the cage. It stopped and I entered and pulled the cord three times, signalling the winder driver to let me off at that level.

My signal was ignored. For over an hour I rode the cage as it stopped in the total darkness between levels. The light on my helmet lamp illuminated names carved into the timber support walls to the shaft as long ago as 1900.  Passing each plat I yelled to be saved, fearing that if the cage went to the very bottom I would be drowned by groundwater. Finally, someone on a plat heard my cries, belled the winder driver, and I was saved.

vertical mine shaft

 It was not unheard of for a machine miner drilling into a recently exploded face to detonate an unexploded stick of gelignite, and have the drilling machine blown back through his body.

The following long vacation I applied for a job as a machine miner at the now infamous blue asbestos mine at Wittenoom Gorge. In those days masks were unheard of. I was unsuccessful in my application, which is why I am here today to write this.

Asbestos mining

 Instead, I obtained a job as technical assistant to the manager of a gold mine at Nullagine, further north. I had a good knowledge of treatment plants as my dad was a mining metallurgist. The treatment plant contained two huge thickener tanks filled with a deadly solution of sodium cyanide used for dissolving the gold. One day I dropped my watch into one of the tanks. I stripped off to my underpants, took a deep breath and dived in and retrieved it from the bottom.

Thickener

I might add that in 1948 while I was living in Norseman aged 9, there was a huge waste dump at the Phoenix gold mine site.  It contained all the left-over waste from processing the ore(tailings), and is still there today. It is 40 metres high and contains 4,000,000  tonnes of cyanide contaminated tailings.

One day with a mate I walked into the dump area where cyanide sludge was being discharged at the top by pipe from the treatment plant. There was no fence or warning signs.  I commenced to climb up one of the steep corners to see what was at the top and became stuck on a vertical section about halfway up.  I could go neither up nor down. If I had fallen, I might not be writing this today. My mate managed to find some mine workers and in due course, I was rescued and suitably admonished.

Phoenix Tailings Dump

 

My mum always used to say that I had the luck of the Irish.

Anyway, those were the days of wine and roses for me, when you had to look out for yourself, and the devil take the hindmost. There were no yellow jackets, nor white hard hats, nor COVID passports.

 

 

 

 

 

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