The Seated Liberty Half Dollar is a significant piece of United States coinage that was minted from 1839 until 1891. This coin is a part of the broader Seated Liberty design series, which also includes the half dime, dime, quarter, and dollar coins. The design was created by Christian Gobrecht, who served as the Chief Engraver of the United States Mint, and is notable for being one of the longest-running coinage designs in U.S. history.

### Design
- **Obverse:** Features the iconic image of Lady Liberty seated on a rock, holding a shield with her right hand (emblazoned with the word "LIBERTY") and a liberty cap on a pole with her left hand. This imagery symbolizes vigilance and the readiness to defend liberty. The date of issue is typically found at the bottom, beneath Liberty.
- **Reverse:** Initially, the reverse featured an eagle holding an olive branch and arrows, surrounded by the inscriptions "UNITED STATES OF AMERICA" and "HALF DOL." Over the years, there were slight variations in the reverse design, including changes in the eagle's depiction and the addition of a scroll with the motto "IN GOD WE TRUST" in 1866.

### Varieties and Key Dates
The Seated Liberty Half Dollar series encompasses several varieties based on modifications to the obverse and reverse designs:
1. **No Motto (1839-1866):** Early coins did not include the "IN GOD WE TRUST" motto.
2. **With Motto (1866-1891):** Following the addition of the motto to U.S. coinage in the mid-19th century, it was included on a scroll above the eagle.
3. **Arrows at Date (1842-1853, 1873-1874):** Coins from these periods include arrows around the date to signify a change in the coin's weight.
4. **Rays Around Eagle (1853):** The reverse included rays around the eagle for this year only.

### Specifications
- **Metal Composition:** 90% silver, 10% copper
- **Weight:** Varied slightly over time but approximately 12.44 grams in its most common form
- **Diameter:** 30.6 mm
- **Edge:** Reeded

### Historical Context
The introduction of the Seated Liberty design reflected a period of growth and change for the United States. It saw use through major events such as the Civil War, the westward expansion, and the Industrial Revolution. The coin's lengthy production run means that it was a familiar sight to several generations of Americans.

### Collectibility and Value
- **Condition:** As always, the condition of the coin greatly influences its value, with well-preserved examples demanding higher prices.
- **Rarity:** Certain years and mint marks are more scarce than others, making them particularly valuable to collectors. Key dates include the 1853 With Rays, 1870-CC, and 1878-CC among others. Coins with low mintage numbers or those from the Carson City mint (CC) are especially sought after.
- **Varieties:** Collectors often seek to acquire coins from each sub-variety in the series, adding an additional layer of challenge and enjoyment to collecting Seated Liberty Halves.

The Seated Liberty Half Dollar holds an esteemed place in the panorama of American numismatics, not only for its beauty and the craftsmanship of its design but also for its representation of the nation's values and historical epochs during its circulation.