With the promotion of his latest movie, 'Blood Diamond', Leonardo DiCaprio revealed that this project was more than just one of those things one does for money. After spending the last five months in Africa and Mozambique, with his co-star Djimon Hounsou, Leo really got involved in all that the film is supposed to stand for.

The plot revolves around a smuggler/journalist trapped in Africa and whose only ticket out is a very rare pink diamond, hidden somewhere. But the bigger picture includes the 'conflict diamonds' in general, sold and used to buy weapons and to sponsor civil wars. This particular instance that the movie refers to is that of what happened in Sierra Leone in 2002, when more than 50,000 innocent people were slain.

In a recent promotional interview, DiCaprio said that, although 'Blood Diamond' is not meant as a direct attack at the jewelry industry, it does warn people to make sure they never purchase any of these conflict diamonds that are still on the market.

'From my conversations with Global Witness or Amnesty International, you have to go into the stores and buy these diamonds and ask for a certificate, ask for some sort of authentication that this isn't a conflict diamond. That's one of the biggest ways that this whole process can be put to a stop', Leo's advice to diamond lovers all over the world sounds like.

As for him, he never liked to offer 'a girl's best friends' to anyone, save his mother. 'Well, I don't remember the last time I have [bought a diamond]. My mom is the only person that I would buy something like that for, and for a while now she hasn't wanted one'.

'Blood Diamond', also starring Jennifer Connelly opens in all theaters in the US on December 8th. CLICK HERE to see the trailer.