We are used to trust scientists. We refer to them when we want to ground our words, we quote some quotes and involve experts to solve various issues. But they are still ordinary people just like us and can be wrong at times.
The idea of turning Plumbum to gold was not really obsolete like today and this is easily explainable. The first experiments on chemistry were more that promising: some mixed materials changed colors, exploded and flew away, grew and collapsed. The conclusion was obvious: why can’t a rough metal become a shiny yellow one? People started searching for a specific reagent which was also called the “Philosopher’s Stone” which remained just a blind hope along with the “Elixir of Life”.