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Definition: This error type occurs when compacted die fill ("grease") falls out of a recess in the die face and onto a planchet. The plug of hardened material is then struck into the planchet, leaving an incuse impression of whatever design element the plug had molded itself to. Letters ("dropped letters") and numbers ("dropped numbers") are the most common elements duplicated in this fashion. If the plug remains next to the same die it fell out of, and if it doesn't flip over, the dropped letter/number is oriented the same way as its normal raised counterpart. If, however, the filling falls against the opposite die or flips over, the impression is mirror-image. Most dropped fillings are normally-oriented.