I'm not very experienced in coin collecting especially when it comes to errors and the like. So I would appreciate some help with these coins. I don't remember when I found these but I saved them because they looked a bit different, there's two cents and a dime. First is a 1987 D cent. Just seems to have an odd texture to it. Maybe I'm just seeing things here. then there is this 1996 D. Has some odd very small bumps on it. and finally the dime, which has some odd copper colored areas on it.
First Two are just plating blisters. Second one is staining from the environment. Plating blisters are a type of error found exclusively on copper-plated zinc Lincoln cents produced from 1982 to the present. These blisters form during the striking process when expanding gas, generated by heat and pressure, pushes up the copper plating. For plating blisters to occur, there must be a weak bond between the copper plating and the zinc core, often due to contaminants within or under the plating. Key points about plating blisters: - Types: Blisters can be circular or linear. Linear blisters often run parallel to planchet striations. - Appearance: They are hollow and should not be confused with solid blisters caused by subsurface corrosion (zinc rot). - Formation: The blisters form as gas expands beneath the copper layer during striking, lifting the plating. - Common examples: Coins from various years, such as 1984, 1985, 1992, 1995, 1996-D, 2007, and 1986-D, have shown both circular and linear blisters. - Distinguishing from corrosion: Solid blisters from corrosion are caused by gas under expanding metal, often due to a tear in the copper plating that allows oxygen to reach the zinc core.
