This turns out to be based on a conspiracy theory:

"Current public perception of diamonds is the direct result of a masterfully executed marketing campaign by De Beers that began in 1938, not inherent scarcity or value. If you've read the article by Edward Epstein (you really should), you know all of the gory details. Isn't it amazing (and scary) how brainwashed people are about the "value" of diamonds, even though they're not actually worth that much?"

Thus, without further investigation, we can conclude that the writer is a croony crackpot (I don't know if thats a thing, but, anyhow)

right?