Some time ago i watched one of those BBC History shows (Medieval Lives) with Terry Jones, the Episode is named “The Philosopher”

http://www.youtube.com/watch?v=ZTf2EzTd1TE

At 6:30 he tells us that a Lead shielding , in an experimental reactor in Siberia, was turned to Gold.

I haven’t been able to find more about that case.
How could that be possible, as far as i know that only works with a Mercury Ispotop.

Could it bee that it happened in steps from one element to another?

Well here’s a quick quote from wikipedia on nuclear transmutation.

http://en.wikipedia.org/wiki/Nuclear_transmutation

“It transpired that, under true nuclear transmutation, it is far easier to turn gold into lead than the reverse reaction, which was the one the alchemists had ardently pursued. Nuclear experiments have successfully transmuted lead into gold, but the expense far exceeds any gain.[6] It would be easier to convert gold into lead via neutron capture and beta decay by leaving gold in a nuclear reactor for a long period of time.
More information on gold synthesis, see Synthesis of precious metals.
197Au + n → 198Au (halflife 2.7 days) → 198Hg + n → 199Hg + n → 200Hg + n → 201Hg + n → 202Hg + n → 203Hg (halflife 47 days) → 203Tl + n → 204Tl (halflife 3.8 years) → 204Pb (halflife 1.4x1017 years)”

You would have to ask someone knowledgeable about nuclear reactors whether the conditions inside a reactor are sufficent to cause this kind of transmutation but even if it did I suspect the quantities would be microscopically small.

Yes, I know, but it would be interesting to find out how this happened, because as you already wrote, it would be easier to do it the other way round.

Google is your friend

In 1980, Glenn Seaborg was successful in transmuting minute quantities lead to gold, possibly via bismuth. In 1972, Russian scientists found that the lead shielding of an experimental nuclear reactor near Lake Baikal in
Siberia had unexpectedly turned to gold!

Unfortunately such gold is likely to be radioactive, and would decay back to stable lead, whilst releasing dangerous radiation.

There are very few hits on this topic. This thread was seventh on the list. I have doubts about the lead shielding turning into gold: more likely some of the lead on the shielding turned to gold, but as noted above it would decay quickly and release dangerous radiation while doing so.