Blood diamond trading is less a problem now than it was decades ago. Most jewellery companies today are running ethical fine jewellery businesses. Ethical jewellers source their materials (diamond stones/ metals) ethically, e.g. they will check if the stones have been involved in African conflicts before. Stones and all other materials are sourced from fair trading. With a large stock of jewellery, companies will only use gold produced without mercury or cyanide and fully traceable diamonds as their raw materials. Exploitation of labour does not exist anymore. Employees have more welfare and respect from their employers. Moreover, the production process of jewellery is becoming more environmental friendly; as for example, Beaucoco recycles plastic and use it in its jewellery.
The article can be found here:
http://www.bbc.co.uk/thread/features/silverlining/