The 1-ounce gold Proof 2011-W American Buffalo $50 gold coin illustrated is counterfeit as is the NGC holder and the label on which the grading information is imprinted.

This purported Proof 2014-W 1-ounce gold American Eagle is actually a counterfeit missing the W Mint mark. The NGC holder and grading insert label are also fake.

Immediate points that something is amiss with this 2014-W 1-ounce gold American Eagle is that the piece illustrated has Proof surfaces but the grade is for a Mint State coin.

Counterfeit Proof American Eagle and American Buffalo 1-ounce gold $50 coins have been reported in Ohio encapsulated in fake Numismatic Guaranty Corp. plastic holders with counterfeit grading label inserts.

The counterfeits surfaced in the greater Columbus area at a retail coin shop whose owner wishes to remain anonymous.

The dealer reported March 21 that a customer came into his store a few days earlier to sell a purported NGC-certified 2014-W American Eagle 1-ounce gold coin. While the piece initially appeared like any other Proof American Eagle, further examination showed that the encapsulated coin, while exhibiting Proof surfaces, was missing the W Mint mark of the West Point Mint.

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The grade on the grading label insert also designates the coin's condition as MS70, for Mint State 70, a grade that would not apply to a Proof coin. The MS-70 grade would apply either to a bullion coin, struck properly with no Mint mark, or to the Mint's Uncirculated version, often termed Burnished Uncirculated, which is marketed to collectors and carries a W Mint mark.

The dealer checked the certification number of the questioned piece on the NGC website. The certification number on the counterfeited gold piece is registered to a genuine NGC MS-70 Burnished Uncirculated 2014-W American Eagle $50 coin.

When the dealer compared the diagnostics on the suspicious coin against a known genuine example in his inventory, he determined that some design elements on the suspect coin were incomplete, including detail on the eagle feathers. The dealer also determined the suspect coin and holder together weighed 10 grams lighter than what a genuine coin in its encapsulation would weigh.

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The dealer also determined that a purported Proof 2011-W American Buffalo 1-ounce gold coin that the same customer brought in was also counterfeit, along with its holder and grading label insert.

Max Spiegel, vice president of sales and marketing for NGC's parent company, Certified Collectibles Group, said the grading service has previously encountered similar counterfeits.

"We've seen these on occasion," Spiegel said March 21 via email. "Both the coins and holder parts are counterfeit. The quality of these counterfeits is generally quite poor. For example, the $50 Gold Eagle is labeled MS 70 but looks like a PF coin (and does not appear to have a 'W' Mint mark).

"We encourage people to always check the Verify NGC Certification feature on our website (https://www.ngccoin.com/certlookup/). Since October 2008 we have imaged nearly all of the coins that we have graded as a measure against counterfeiting and tampering. You can compare a potential purchase to these images to make sure that they match. In the case of the images you sent, they do not match the ones we have available on our website.

"If a legitimate NGC certification number is copied on a counterfeit holder (or if there is some other issue related to that certification number) we will put a note 'Contact NGC Customer Service' in our Verify NGC Certification tool to advise a prospective buyer that they should contact NGC Customer Service.

"We are researching both the origins of these counterfeit holders as well as enhanced security features for our holders. Counterfeit holders not only infringe upon our registered trademarks, but also violate the Hobby Protection Act of 1973 and the Collectible Coin Protection Act of 2014. We will consider all available options to pursue those who counterfeit our holders."