[ngm-hn]

Most of the article seems critical of the diamond industry. Have they not done people a service by providing them with a nice product that they can enjoy?

There are certainly moral problems with how they built their empire, but why are clever marketing and aggressive pricing bad things? The former is simply how you tell people about new products. Remember diamonds went from being owned by almost no one to being owned by lots of people. If those rings make them happy, then why is it our business?

How is DeBeers marketing any different from Apple marketing?

Of course, the article does do a good job in warning people that their diamonds may have little resale value. But that's a risk most buyers are willing to take. After all, most non-divorced people don't sell their wedding and engagement rings.

[Quizz]

It's bad because it's a vertical cartel, from mining to distribution. Cartels are illegal in that it limits the free market using artificial price controls. It's the artificial price controls that are illegal. Apple faces competition from Android, RIM and Win8. DeBeers diamonds do not face any competition from any other diamond producer because they spent 50 years establishing their network for "gem" quality diamonds. DeBeers is beyond marketing. Why did the U.S. government go after Microsoft? Standard Oil? Why did the U.S. prevent AT&T from merging with TMobile?

[ngm-hn]

Well no, that argument does not work. Apple is the monopolist supplier of iPhones. And it charges whatever price it wants for iPhones. If DeBeers is a sole (or near sole) supplier of a product, then Apple certainly is.

Further, DeBeers must face the same competition that Apple faces. In these comments, we see lots of people looking at other gemstones (sapphires, etc) in place of diamonds. The other gemstone producers compete with DeBeers in the same way that other smartphone producers compete with Apple.

I'm not sure it's helpful to reason from the fact that something is illegal to why it is wrong. Sort of like the joke about the three storekeepers in jail: The first charged higher prices than everyone else and was convicted of price gouging. The second charged lower prices than everyone else and was convicted of dumping and cutthroat competition. The third charged the same prices as everyone else and was convicted of collusion. Laws will be made against all kinds of things, and there are many incentives (e.g. law firms revenue) to make laws against very profitable enterprises.