The coin you have described is a 1841 Braided Hair Cent, minted in Philadelphia (Mint Mark: P). This particular piece is a proof strike, a special type of coin produced with a high level of detail and a polished finish, intended primarily for collectors rather than for general circulation. The coin, classified under the denomination of 1¢ (One Cent, Penny), features a stunning design characteristic of the Braided Hair series, which showcases Liberty's flowing hair adorned with a headband. The series is known for its intricate details and represents a transitional period in American coinage. This specific coin measures 27.5 millimeters in diameter and weighs approximately 10.89 grams, composed primarily of copper. Remarkably, it has a mintage of 0, indicating that no coins of this specific type were officially produced, making it an exceptionally rare piece. Please note that the specified dimensions for width and height are recorded as 0.00000000, which suggests that these measurements may not be relevant for this particular collectible coin. Overall, the 1841 Braided Hair Cent proof represents a noteworthy addition to any numismatic collection, particularly for enthusiasts of United States coins, given its rarity and historical significance.