written by Ole Nikolaysen
I am intrigued and fascinated by gold. I was equally intrigued and fascinated by this talk about gold prospecting kindly given by Mike Potter. Mike is a professional geologist working as a prospector for large mineral companies. He did not hold back on his vast experience and took us from an overview about the properties of gold until we literally could hold samples in our hands. Little did I know that all the gold so far mined from 3000 BC till today would make a cube a mere 20 metres on each side. Most gold produced is used for jewellery. In fact, nowadays more gold is being used each year to make jewellery than is actually produced from all the world’s mines combined.
The most exciting part, for me at least, was the journey made in the search of gold in far away Ecuador. With the help of more then a hundred slides we experienced the first exploration in the jungle on mule back. Somebody present could not imagine it without a helicopter until we saw the wooden helicopter landing pad! Then we witnessed the initial panning install streams until a promising valley was found. It took more than 400 drill holes to define a future mine. Next 3000 cubic metres, each with a gram of gold, were excavated each day and trucked away to the processing plant to recover $35,000 per day 362 days a year, three days off. Of more than 2500 tonnes of gold mined worldwide a year this particular mine produced a mere one tonne.
It was quite a job for Mike to reduce his extraordinary knowledge and hundreds of slides into one hour talk and he could have continued for many more hours. He had planned to teach us the art of gold panning, but when it came to it the listeners were more interested in the wine and tapas which at that time were tempting us from the tables behind. The St. Gothard hotel in Erts graciously provided us with a spacious room with good acoustics for this event.
I’m looking forward to listening to more fantastic exploits hidden in the heads of our Club members.
Gold Platinum Silver Palladium Copper
Chemical Symbol Au Pt Ag Pd Cu
Density (g/cc) 19 21 10 12 9
Melting point (°C) 1060 1770 960 1550 1080
hardness (Moh’s scale) 2.5 2.5 3.5 4.8 3.0
electric cond (10⁻⁶cm⁻¹Ohm⁻¹) 0.45 0.10 0.63 0.10 0.60
Approx. crustal abundance (ppb) 3 5 80 6 70.000
Approx. current price (US$/Troy oz) 350 680 5.0 180 0,055
Published in the Inter-Comm Autumn 2003