What a coinkidink, I just finished watching episode 2 of "Connections" with James Burke which mentions this in the beginning of the episode, when talking about the invention of currency. The article from Egypt Today doesn't seem to mention the discovery of touchstone (which the episode does), which seemed like an important detail of "why gold?".
Seems it's available on the Internet Archive too: https://archive.org/details/james-burke-connections_s01e02