Like lots of other people I was embarrassingly unaware of the issue until it became the subject of a film in 2006. In my defence, I wasn't looking to get married at the time so I had no real need to buy a diamond (I'm sure I would have looked handsome with a diamond stud in my nose, but it was beyond my means).
11 years after the film, it still appears to be a problem, at least according to Amnesty International who say the industry still helps 'fund devastating civil wars in Africa'.
Three years prior to the film coming out was the development of the Kimberley Process Certification Scheme which you may well have heard about.
However, according to Amnesty International (again):
Despite its pledge to support the Kimberley Process and Clean Diamond Trade Act, the Diamond Industry has fallen short of implementing the necessary policies for self-regulation. The retail sector in particular fails to provide sufficient assurance to consumers that the diamonds they sell are conflict-free.
Their plea is to help them survey retailers to find out what is happening on the ground.
My own research was more positive than I was expecting.
I looked at five of the UK's high street jewellers and found all of them offer a guarantee on their website that they don't sell 'blood diamonds' (I looked at H Samuel, Beaverbrooks, Ernest Jones, Goldsmiths, F Hinds.
I then looked at Amazon, which has a vast choice of diamonds.
It's important to understand that Amazon sells items direct and it also allows others to sell through its third party 'Marketplace'. Amazon's big diamond brands like Miore or Naava both guarantee to be conflict free, so if you want to be sure I would buy direct from Amazon.
There was an article 10 years ago which suggested that it is harder to offer such guarantees with third party sellers, but that's about all I could find. Most items on Amazon have clear descriptions, and you can always contact the seller if you find a bargain which you aren't sure about.
Other big online diamond sellers which offered conflict free guarantees included Diamonds Factory, Diamond Heaven and Purely Diamonds.
I'm certainly not saying that the issue of blood diamonds has gone away but I was pleased to see how easy it is for UK shoppers to find a diamond engagement ring which is guaranteed to be conflict-free.