The coin in question is a 2007 Sacagawea Dollar, minted at the Denver mint and marked with a "D" mint mark. As part of the United States currency system, this coin has a denomination of one dollar, or $1. It is composed of manganese-brass, which gives it a distinct color and durability. This particular Sacagawea Dollar features a diameter of 26.5 millimeters and weighs 8.07 grams, adhering to the standard specifications for this series. The 2007 mintage for this coin was 3,920,000, making it a relatively common issue among collectors. In terms of design, the Sacagawea Dollar typically showcases a depiction of Sacagawea, a Native American woman who played a crucial role in the Lewis and Clark Expedition. The coin is notable not only for its historical significance but also for its contribution to American numismatics, representing an effort to honor Native American heritage. Whether for collecting or spending, this coin holds value not just in its face amount but also in its cultural and historical significance as part of the ongoing story of the United States.