alt Hacker NewsNasa preferred gold (more specifically copper plated with nickel and then plated with gold) https://en.wikipedia.org/wiki/Voyager_Golden_Record
Nasa preferred gold (more specifically copper plated with nickel and then plated with gold) https://en.wikipedia.org/wiki/Voyager_Golden_Record
To be fair, that's not simply an archival disc, but also something explicitly intended to be readable by intelligent life elsewhere in space. The encoding of data was optimized for simplicity above all else.