The U.S. and global investors should be wary of precious metal bars and silver and gold coins. The Wall Street Fraud Watchdog, the premier U.S. advocate for investor protection and due diligence for high net-worth individuals, recently announced that Chinese counterfeit coins and precious metals already make up a multi-billion dollar industry. And the threat is growing.

"We are saying this is going to be another train wreck for investors, who thought they were buying a safe investment," explained the Wall Street Fraud Watchdog. "In the instance of counterfeit Chinese U.S. silver dollars, gold coins, or precious metal bars, the investment could be worth zero."

Experts fear that Chinese counterfeit coins and metals could have disastrous consequences in an already sinking global economy. China has long been infamous for providing the world with knock-offs and counterfeits, and according to Global Piracy & Counterfeiting Consultants, over 10 percent of China's gross domestic product comes from counterfeits.

"If it's not knock-off pharmaceuticals that can kill people, it's high tech smartphones or electronics," warned the group. "Our new worry is pretty obviously related to Chinese counterfeiters bankrupting innocent precious metal or coin investors, with what could be their life savings."

The Watchdog has some helpful tips for investors to avoid buying counterfeit metals. It urges consumers to purchase only from reputable dealers and brokers and advises against ordering any coin or precious metal bar on the internet. Each purchase should come with a receipt and a money back guarantee. It further advises investors not to buy gold or silver coins at flea markets or yard sales.