These coins are 8.33% Nickel Balance Copper. The set consists of Oregon, California, Minnesota, Kansas, and West Virginia state Quarters. All from the 2005 year of minting. A six coin proof cioin set, Certificate of Authenticity and original mint box. Distributed by the United States Mint. These coins are produced from carefully selected planchets, or coin blanks that have been burnished to a high luster. The polished blanks, which are carefully handled to minimize scratches and abrasions, are struck on specially adapted coining presses. Each coin is struck at least twice to bring forth the the most minute detail with remarkable clarity.