Russian billonaire, Oleg Deripaska, normally tries to avoid the media spotlight. But Tim Whewell was able to spend some time with him and gain an insight into his life.
Mr Deripaska started off as a metals trader in Russia in 1992
Having spent a couple of days in the company of the 164th (until recently ninth) richest person in the world, I can report that he knows an awful lot about the properties of silver foil, plans to make Russia into a nation of white-van lovers, and is partial, late of an evening, to a cup of special Siberian herbal tea.
I can report nothing about the view from his spectacular yacht, the Queen K, where he famously entertained Lord Mandelson, the speed of his private jet, or the furnishings in any of his many homes - because that was not the "vulgar" subject matter the Aluminium King of Russia, Oleg Deripaska, had in mind when he invited me on a private tour of his empire.
No. We were going to roll up our sleeves, put on our safety glasses and hard hats - and talk production.
We were interested in the source of wealth, not its trappings.
In the 85% automation level on the assembly line at GAZ, his car plant at Nizhny Novgorod on the Volga - the 3,200 welding spots on his latest model, the Volga Siber - the accuracy on his quality control apparatus of one micron - a thousandth of a millimetre, the 415,000 amp current that electrolyses the alumina at his smelter in Sayanogorsk in southern Siberia - do not stand too close - and the scorching 730 degrees Celsius inside the furnace.
Vladimir Putin owns a 1956 Volga - will Mr Deripaska's model be as loved?
These are statistics to conjure with, not those you may have heard before about Mr Deripaska - how he was worth $28bn (£17.5bn) last year and only $3.5bn (£2.1bn) now.
In any case, he disputes those figures.
He never had anything like as much as they say, and anyway, he parries jovially as we sit back in his company's Swiss-style chalet high in the Sayan Mountains, do I know how much money I have got?
Touche! I am stuck.
On the one hand, I feel a certain moral obligation to stand up for that portion of the world's population that does need to keep abreast of its financial affairs.
On the other hand, do I really want my new friend to think I am some kind of Fagin, sitting up half the night over piles of pennies?
From this you will probably have gathered that Mr Deripaska and I quickly established an easy, bantering relationship.
He not only looks much younger than his 41 years, he is positively boyish in his energy and enthusiasms.
And so we bound down the assembly line at GAZ discussing axles and suspension, touching on the benefits of the Toyota Management System, debating why Britain lets its engineering talent go to waste.
Later in the week, four time-zones to the east, he diverts his helicopter to take me low over the breath-taking Sayano-Shushenskaya dam, once the highest in the world, the source of all those amps in the smelter.
All the time he is pointing down excitedly at the spruce-covered hillsides, telling me what geologists might find next under Siberia.
He has cornered the market in aluminium, but that is not enough. Down there is copper. Further on, molybdenum.
The helicopter's nice, furnished with cream leather sofas. But we are asked not to film it. For security reasons and also, you will remember, because that is not the kind of thing we are interested in on this trip.
He tells me about all the extra trees he is going to plant around his factory, down where the mountains meet the bare steppe. He tells me about the computers he is giving to schools.
Only late at night in the chalet - and Mr Deripaska likes late nights - do we turn briefly to darker, more emotional matters.
UK Business Secretary Lord Mandelson was famously entertained on his yacht
"Why," he asks suddenly and insistently, "do the British press hate Peter Mandelson so much?"
And again I am stuck. Because while I can think of many possible answers to this question - all intriguing enough to occupy a happy hour over a pint down at my local - I am talking now to Peter's friend, a guy I am trying to bond with.
And so we return to the subject of whether his light commercial vehicle, the Gazelle, could have been improved by technology from the British firm he once owned, LDV.
I will be honest. I am not very interested in vans.
But I liked Oleg Deripaska.
I liked his teasing grin. I liked his ready laughter. And I appreciated his delicacy in not wining and dining me.
Our trip to Siberia was good for both our reputations - because, in these stern days of expense-related scandals, I have almost nothing to declare - only his herbal tea, the master-class in foil making, the unforgettable swoop in the helicopter - oh, and a tiny souvenir ingot of the first aluminium from his smelter.
As for a journey on a gigantic yacht - as Frank Sinatra almost sang in "Who Wants to be a Millionaire?" - I am so glad I did not.
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