Diamonds are for suckers.

Diamonds are forever. That's because you'll never be able to sell them. The linked article brilliantly explains the 'perceived value' that the De Beers Diamond Company keeps on the entire diamond market. Using virtually every diamond and jewelry store in western society to maintain the outrageously high market value of diamonds by selling new diamonds at a 100-200% markup, and generally refusing to buy back 'used' diamonds.

The retailers usually cite the standard excuses such as "we can't match the sentimental value your diamond holds for you". But the truth is that they know that 90% of all diamonds in the world are owned by people just like you and me. And if there suddenly opened up a sales outlet for those 'used' diamonds, the market could be flooded overnight, and prices would plummet instantly. The result would be that the marketing ploy we've heard so many times that "diamonds are a solid investment" would suddenly be seen as the BS that it actually is. Sure, your diamond is a great investment as long as you never try to sell it.

And that reminds me of another interesting news story. Remember the one about the diamond ring left anonymously in an unlocked car? My guess is that the owner of the ring was jilted by his sweetheart, which was tramatic enough. But then he found out the hard way that the expensive ring he just purchased was worth next to nothing on the used diamond market. Rather than jump through various hoops to try and recover a fraction of his investment, he cut his losses entirely in a less emotionally exhaustive way.