A COIN collector is sharing how to spot one of the rarest errors a coin can have.

Shaun runs the TikTok BlueRidgeSilverHound, where he posts about rare coins and bills he comes across.

In one of his latest TikToks, he showed viewers an example of an uncommon error called the double denomination.

This is basically two coins in one and happens when an already-produced coin is struck with a die meant for another coin.

The 2007 Montana quarter appeared to be a bit smaller than a regular quarter as some of the details around the edges of the coin were cut off.

On the reverse of the coin, there are some odd lines and imprints behind the bison skull and mountain skyline that are on every Montana quarter.

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Shaun explained that this quarter was struck on an already-produced Jefferson nickel.

The lines and imprints on the back of the quarter are actually the remnants of the Monticello peaking out from underneath the Montana design.

In the video, Shaun showed one of these quarters that sold for $6,325 in 2012.

However, on the same site, there is a listing for the same coin from 2015 that only sold for $2,500.

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Both coins were in extremely good shape with a grade of 64. The highest a coin can be graded is a 70.

Coins with lower grades will typically sell for less.

The most valuable quarters

There's a chance you may have a quarter lying around your house that's actually worth thousands of dollars.

An 1860-S quarter in the Liberty seated series sold for $4,265 on eBay.

And this coin could be worth up to $57,085 if in an “uncirculated (MS-60)” grade, according to USA Coin Book.

Its value comes from the aftermath and the effects of the US civil war, which drove circulation, particularly in the western states.

Only 22,850 1872 CC Liberty quarters were minted, making them extra valuable.

If you happen to have an 1872 quarter – you’ll want to look out for a “CC” on the reverse of the coin because this version contains the lowest mintage in the Liberty seated quarter year.

The CC stands for the mint location, Carson City.

One example certified by the Professional Coin Grading Service in an “F 15” grade sold for $5,600.

A 1916 Liberty Standing quarter sold for $9,500 online, mostly due to the scarcity of this coin, as only 52,000 were minted.

Also, this one has been certified in a higher grade of XF 45, the seller in the listing claimed.

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Your gold dollar coin might actually be worth $66,000 if it has one important detail.

Plus, check your change to see if you have a penny worth $300,000.

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