The 2015 US Mint Silver Proof Set includes coins with a composition of 90% silver, struck with a proof finish in San Francisco. This set comes with a box and Certificate of Authenticity from the U. The coins are uncirculated and ungraded, making it a desirable addition to any coin collection. The set features a variety of coins from the United States, showcasing the Mint’s craftsmanship and attention to detail in producing high-quality coins for collectors and enthusiasts.