The Kamioka mines: from silver to supernovas

Part of the Kamioka zinc mining and smelter complex

Just after posting about the Kamioka Railway another photo from that 2006 set piqued my interest. Up there in the mountains the landscape looked blasted not just by winter but by something more. It was the kind of lonely place where you would not expect to find major industry, so this sight was quite surprising. Even more surprising is the history associated with this photo.

According to some sources mining and refining of ores in Kamioka dates back to 710 AD and only closed in 2001. Undoubtedly the mine was a major reason for the existence of the Kamioka Railway. Refining of zinc still continues to this day under the parent Mitsui Kenzoku zaibatsu.

Gold, silver, copper, zinc and lead were all dug out of the rock here. Unfortunately, the process released cadmium into the river, which, when taken up by the rice that was grown in the river, caused the terrible itai-itai disease - meaning "It hurts! It hurts". Cadmium poisoning has a number of terrible effects on the body, including the softening of bones and kidney damage. The corporation and government were forced to engage in a large clean up operation which primarily involved preventing the escape of further cadmium contamination at the source.

But the history of the mine doesn't end there. Hidden away a kilometre underground in the mine is a huge tank of ultra-pure water and extremely sensitive photodetectors. Called the Super Kamionkande Experiment, its purpose is to detect subatomic particles called neutrinos. These particles only interact very weakly with matter, but when one does collide at very high speed with an atomic nucleus or electron in the water it can accelerate it to beyond the speed of light in water and produce a detectable flash of Cerenkov radiation.

Super Kamionkande has detected neutrinos generated by fusion within the Sun and by the supernova 1987a.

So this is a story of curiosity, discovery, wealth, suffering and enlightenment.

Comments

One night in Canberra

It's the April school holidays and we are too busy to have a break but need one because of that. And because it's the Easter weekend the options are limited, so we just drive down to Canberra for the night. No, this isn't our first trip for 2023. I wrote about Japan on another site . I refuse to wake up early so we depart after 8.30 AM. There is not much to say about the drive except that the clouds seem so low and Lake George is very full. We stop at a rest area and at the lookout up the hill to take it all in. Everyone is hungry so we first stop in Dickson and then can't think of anything to eat, so I drive us to Civic, where we can't decide and end up eating at the Singaporean Killiney Kopitiam branch. The Canberra Centre has nice shops. I dream of getting an iPad from the Apple Store, we buy a blanket and toothbrushes from Muji and wish that Lego wasn't so expensive. Nothing we can't get in Sydney, but then we rarely go out shopping in the city. It...

IKEA Museum

We have a packed itinerary today. Flat packed and assembled with an Allen key. There are patches of snow on the ground that weren't there the previous evening. We are a bit sad to leave the Duxiana after the comfy beds and the breakfast of cold cuts, fruits and hot waffles. I tried the Swedish caviar on my boiled egg. It was... Interesting. I was very disappointed to realise that, after talking it up for months, I had forgotten the Disgusting Foods Museum in Malmö yesterday. Too late now. We catch another Oresundstag train, for a bit over an hour. Past yesterday's Lund, past increasingly white fields and towns to Älmhult, home of IKEA. The conductor warns us that the train will split in two so we have to move carriages forward. Unfortunately, there we no spare sets of chairs for all of us. The IKEA Museum showcases the history of the furniture company, along with temporary exhibitions. One of these was "Hacking IKEA," about using IKEA ob...

Springs, castles and the end of the line

I am never happy to stop before the end of the line. It irritates me to know that there is still somewhere unexplored lying ahead. So when I only got as far as Gujo Hachiman on the Nagaragawa Railway last year I knew I needed to return for more. Especially as this private third sector railway is, by its very nature, always at threat of closure due to low patronage. But did Gujo Hachiman deserve another visit? Sure it's a nice enough town, but had we missed out on enough last time to return? Mum's trip provided the excuse. I originally planned the Oito line, which wI'll be partly closed when the Shinkansen line is extended to Kanazawa. However, when I thought of special places in Japan that deserved to be shared Gujo Hachiman was at the top of the list. Before we could go anywhere Mum needed her coffee. There was a Tully's Coffee opposite the hotel entrance, so I parked her there while I booked our seat reservations. Mum got her fast train ride on a ...

travelling allrite

Search This Blog