The Gorham Coin A3 mark is found on early silver pieces made by the Gorham Manufacturing Company during the mid-19th century, before the widespread use of sterling silver in the United States. The word "Coin" indicates the piece is made of coin silver, typically 90% pure silver, and the “A3” is a model or pattern number used by Gorham to catalog specific designs. These early Gorham pieces are often handcrafted and highly collectible, representing the company’s formative years and the transition from artisan silversmithing to industrial production.