Collectible coins are often sought after by numismatists for their historical significance, rarity, and condition. The United States issued various one-dollar coins throughout its history, including the Gold Dollar, which was produced from 1849 to 1889, with notable issues like those minted in 1867. The Gold Dollar coins are composed of 90% gold and are highly valued, particularly in well-preserved condition. Collectors often focus on specific years, mint marks, and design variations when assessing the value of these coins.