While many valuable coins can require a keen eye and even a microscope to determine its value, the unique color of this state ...

Here are 20 rare state quarters worth additional value, according to Gainesville Coins, USA CoinBook and PCGS. Keep in mind that “error” coins — the ones primarily included on this list ...

That's because rare state quarter errors can give these coins a higher value. Some can be worth thousands, so grab your ...