About two years ago, I purchased an original bank roll of 1956 Wheat Cents. Upon receiving my roll, I decided that I wanted to see the gems inside. After opening them and looking at a few, I noticed a die crack on Lincoln's head. Over the next few coins, the crack started spreading until a nice die chip had formed. Below are the pictures of these coins as the crack progresses.
(Disclaimer: Some pictures may not be in order of progression.)
OBV

Lincoln Cent Project by jnesbitt82, on Flickr
REV

Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr
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Lincoln Cent Project by jnesbitt82, on Flickr