In jewelry stores on 47th Street and Fifth Avenue in Manhattan, the important trust between merchants has been violated. A 10-ounce gold bar costing nearly $18,000 turned out to be a counterfeit.

The bar was filled with tungsten, which weighs nearly the same as gold but costs just over a dollar an ounce.

Ibrahim Fadl bought the bar from a merchant who has sold him real gold before. But he heard counterfeit gold bars were going around, so he drilled into several of his gold bars worth $100,000 and saw gray tungsten -- not gold.

What makes it so devious is a real gold bar is purchased with the serial numbers and papers, then it is hollowed out, the gold is sold, the tungsten is put in, then the bar is closed up. That is a sophisticated operation.

MTB, the Swiss manufacturer of the gold bars, said customers should only buy from a reputable merchant. The problem, he admits, is Ibrahim Fadl is a very reputable merchant.

Raymond Nessim, CEO Manfra, Tordell & Brookes, said he has reported the situation to the FBI and Secret Service.

To read the complete article, see:Fake gold bars turn up in Manhattan(www.myfoxny.com/story/19578206/fake-gold-bars-turn-up-in-manhattan)

A gold dealer in Manhattan's Diamond District on 47th Street discovered last week that an evidently certified gold bar was in fact more than 75 percent Tungsten.Today we decided to follow up.

Ibrahim Fadl came to New York from Egypt in the mid-70s to earn a Masters in chemical engineering from Columbia University. He's almost certainly the only guy on 47th Street with the periodic table of elements hanging in his office:

Recently, he said, a fellow merchant on 20th street drilled into a 10-oz. bar he'd been sold to check its quality - and learned it was salted with tungsten. He warned Fadl to do the same.Here's what Fadl found:

Ten ounce bars are thicker, making them harder to detect if counterfeited - the standard X-rays used by dealers don't penetrate deep enough.

Plus, the bars had been sealed and numbered. So whoever did this must be running an extremely sophisticated operation, Fadl said.

"It's a shame. This business is built on trust."

The FBI and Secret Service are investigating the incident, but Fadl wonders whether it's within their power to curb the practice, given the incentives involved.

To read the complete article, see:How A Manhattan Jeweler Wound Up With Gold Bars Filled With Tungsten(www.businessinsider.com/tungsten-filled-gold-bars-found-in-new-york-2012-9)