Wrong Planchet Errors: When Rare Quarters Get Struck on Thin Dime Stock
By Alexander Ross
What is the standard dime thickness in mm?
According to US Mint coin specifications, a modern Roosevelt dime measures 1.35 millimeters (approximately 0.053 inches) in nominal thickness, with an official diameter of 17.91 millimeters.
How can I tell if my thin quarter is an error coin or an acid-damaged fake?
Check the coin's surfaces and edge. Acid erosion dissolves metal evenly, leaving gritty, pitted surfaces, faded details, and thinned designs across both sides. A genuine quarter struck on dime stock displays smooth, lustrous fields, normal-sized design elements, and a clean, flat rim profile that failed to fill during the strike.
Can quarters be struck on penny stock instead of dime stock?
Yes. Blanking mistakes have occurred using bronze or zinc cent strip. These errors weigh approximately 2.50 to 3.11 grams depending on the alloy year and display a characteristic copper color across the entire coin surface rather than the cupronickel clad sandwich.
Do I need to send my thin quarter to a grading service before selling?
Yes. Authentication is critical for this category. Because altering coin thickness in home workshops is simple, serious dealers and numismatic auction houses will not buy uncertified wrong planchet or wrong stock errors without slabbed verification from PCGS, NGC, or ANACS.
Alexander Ross has covered the video game industry for a decade, writing deep dives on game design, esports tournaments, VR developments, and gaming culture.
