Metal Trading for the young in the South West
It’s all very well giving advice to young folk via my column in MMTAs Crucible Magazine (as I've been doing for a couple of years), but how about going into the classroom and facing thirty 16-year-olds?
That was my job at The King Alfred School, Highbridge – the main state school in this West of England seaside town, with school buildings dating from the 1950s and 1500 young people looking to be inspired.
But I like a challenge - and was curious to find out how my words would go down in the real world. The invitation was to give a talk about our minor metals first to the economics class, and then business and chemistry. An hour each.
I debated whether to take props but in the end took a 1 kilo bar of silver, two off-cuts of zirconium sheet, two Union flags - and (just in case everything else went wrong) my ukulele.
I opened with a slide of our office metals cabinet (see below) and was surprised by an almost imperceptible intake of breath. ‘This is our sample cabinet at the office’, I told the young people, ‘some of the most unusual elements in the periodic table, taken from real parcels of metal. If we were at the office now, I would put a sample in your hand’. ‘A piece of tungsten in one and silicon in the other maybe'. 'To show how one is dense and heavy – the other voluminous and light'. I then mention the toothpaste-shaped tube of indium (so soft you can cut it with a kitchen knife) present as indium tin oxide in invisible circuits on the glass of the smartphone in your pocket; the phial of thallium (a teaspoon of which if ingested equally would kill the lot of them and be tonight’s excuse not to do homework). That thallium, I say, despite its toxicity, is nevertheless required as a molecule doped in the lens arrays on the optical scanner or school photocopier. Its purpose - to unbend the light and reproduce your class work pixel by pixel. I hold up my mobile phone with its broken glass and wonder aloud, ‘Isn't it amazing that there is not a person in the globe who knows how this works?’ I mean, not how to turn it on and off, but a single human who knows how every part of it works. What a wonderful triumph, I say, of human collaboration! Then I point to the zirconium Van Arkel bar glinting in the photo with its obvious crystal structure which spurs me to mention how not more than two miles away from here, across Bridgwater Bay, the UKs largest infrastructure project would not be possible were it not for the zirconium fuel assemblies containing Uranium 235 pellets.
I digress briefly into describing how through these zirconium tubes neutrons are directed to bombard the U235 atoms, how this element is one of very few low neutron absorbers, allowing the neutron to execute its purpose of splitting the weak uranium atom, releasing more neutrons to split more atoms in a controlled manner to release the energy that heats the water that turns the turbine and so – in due course – produce 3.2GW of constant baseload power for the next 60 years. The plant visible, from Highbridge and Burnham’s answer to Nice’s Promenade des Anglais, might also provide quite a few job opportunities too.
But you can only hold a young person’s interest for so long by strafing them with facts. Time for the ukulele. My idea is to play and sing Tom Lehrer’s The Elements while instructing them to call out any element with the promise I’ll tell them something about it.
Luckily, a girl doing Chemistry class calls out ‘strontium’! (Which enables me to mention that this is the only element to be named after a Scottish town - ‘Strontian’. Even more fortunately I also traded it, so I can talk about how it's reduced from celestine in China, how readily it oxidises (like calcium), how if you were to put some out on the desks it would in a few hours turn to ash. I also then say how it is usually placed in hermetically sealed tins (like baked beans in cans – except made of aluminium) and how - as the stuff is needed in aluminium-strontium alloys - the can is thrown into the melt. Another student shouts out ‘arsenic’! So I tell them about Cornish Pasties – how the tin miners in Cornwall carried their lunch underground holding the crimped expendable crusty edge to avert poisoning themselves with arsenic -particles found while mining tin and copper. I tell them how the Victorians loved green wallpaper coloured by pigments of arsenic oxide which slowly, while writing their novels or running the Empire, killed them through inhalation of fumes. Then someone asks about dysprosium and I was on a roll, telling them about how just 1% is used in permanent magnets to increase thermal properties and prevent wind turbines catching alight from overheating.
‘What is my favourite element?’ someone asks. ‘Rhenium’, I reply, describing the travails by which I came to be involved with this metal. ‘It’s very dense’, ’21gms per cm3, and, this is the cue to bring out my Union flags and stretch out my arms to describe a cubic metre’. ‘In this space is 21 mt. The whole world production of rhenium per year is just three cubic metres worth – and it could all fit in your classroom. Why does the world need it? Where does it come from? Who buys it? Who sells it? Who melts it? Who engineers with it? That is our job – to be interested in all that stuff and to know it. I show a picture of the small 2 kgs Russian crucible in our cabinet made out of rhenium, that came with a parcel of scrap in the 1990s. ‘That was $600 in 1993, in 2008 it was worth $25,000, and today its worth $2000’. ‘Why didn’t you sell it one youngster asks?’ ‘Because it looks like a tooth mug, and I like it’, I say.
We are coming to the close. Teachers do this work every day. I have done two hours and I am rung out. I have only admiration for the teachers and for the young people bothered enough to listen. For a last game I suggest they call out any country in the world and I will tell them something about the resources of that country. ‘Russia!’ someone says. (That’s easy). ‘Slovakia!’ another shouts. (More difficult but not too bad). ‘Somalia!’ a kid shouts from the back.
They’ve got me. Time to go home – and a deserved closing victory for the students having generously given me their time.
Anthony Lipmann
The Crucible 01.04.24
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