So in your view, latinum is kept artificially scarce. Maybe so, but there's no evidence of that, either.
As for diamonds, it is a completely artificial scarcity. Your wife and mine wear diamonds that were mined, but I doubt that a layman could tell the difference between natural and "artificial" diamonds. I'm trained to find the differences. Most people aren't. Practically speaking, natural diamonds are just flawed versions of artificial diamonds.