I hear that it was possible to turn lead into gold like our geat-great grandfathers and grand mothers did. But thist time in a nuclear reacter. Has anybody heard this?

Actually, your great-great grandfathers/mothers never turned lead into gold. Those types of nuclear transformations were not known about until the early 20th century. The goal of alchemy was to turn cheap, easy to get base metals into gold. As our modern knowledge of chemistry and physics tells us, however, their dreams were flat out impossible to do. Still, the field of alchemy led to many great discoveries about chemistry.

 

In modern times it is possible to turn lead into gold, but the process is so inefficient and slow that the money it would take to produce the gold, refine the gold out of the now radioactive base metal, then concentrate it into a useable form would most likely cost in excess of 10 times the current price of gold. (I.E. in order to produce one ounce of gold in a nuclear reactor it would cost in excess of $5,500).

 

So to sum it up, yes you can make gold atoms out of lead in a nuclear reactor, but realistically it would be absolutely useless.