International Precious Metals Institute-  Association focused on precious metals in the world (http://www.ipmi.org/index.cfm)

International Platinum Association - The representing body of the leading mining, production and fabrication companies in the global Platinum Group Metals (PGM's) industry (http://www.ipa-news.org/) 

The London Bullion Market Association - The London-based trade association that represents the wholesale over-the-counter market for gold and silver in London (http://www.lbma.org.uk/pages/index.cfm)

World Gold Council - The Definitive Site for Gold - investment, intelligence, innovative gold science & stunning jewellery trends (http://www.gold.org/)