The Mercury Silver Dime, also known as the Winged Liberty Head Dime, is a ten-cent coin issued by the United States Mint from 1916 to 1945. Despite its official name, it gained its popular nickname due to the obverse depiction of Liberty that many mistook for Mercury, the Roman messenger of the gods, known for his winged cap.

### Design
- **Obverse:** The obverse features a profile portrait of Liberty wearing a winged cap, symbolizing freedom of thought. Designed by Adolph A. Weinman, the coin shows the word "LIBERTY" around the upper edge, the date of issuance at the bottom, and the motto "IN GOD WE TRUST" in the lower left.
- **Reverse:** The reverse displays a fasces, representing unity and strength, and an olive branch, symbolizing peace. The words "UNITED STATES OF AMERICA," "ONE DIME," and the motto "E PLURIBUS UNUM" are inscribed around the fasces.

### Specifications
- **Metal Content:** 90% silver and 10% copper.
- **Weight:** 2.5 grams.
- **Diameter:** 17.9 mm.
- **Edge:** Reeded.

### Minting and Mint Marks
Mercury Dimes were minted at several branches of the U.S. Mint:
- Philadelphia (no mint mark).
- Denver (D mint mark).
- San Francisco (S mint mark).

Mint marks for these coins are located on the reverse, just to the right of the base of the olive branch.

### Historical Context
- The introduction of the Mercury Dime was part of the early 20th-century Renaissance in American coinage, initiated by President Theodore Roosevelt. It replaced the Barber Dime, which had been in circulation since 1892.
- Adolph A. Weinman's design was selected to inspire liberty and freedom, reflecting the optimistic spirit of the era.
- The coin's production spanned the periods of both World Wars, serving as a testament to its era’s challenges and resilience.

### Collectibility and Value
- **Key Dates and Varieties:** Certain years and mint marks are highly sought after, including the 1916-D, one of the rarest and most valuable dimes in American numismatics, due to its low mintage of just 264,000 coins. The 1921 and 1921-D dimes also command a premium, as do Full Bands (FB) versions, which feature fully detailed horizontal bands on the fasces.
- **Condition:** As with all collectible coins, condition is paramount. Coins in "Fine" condition or better, especially those with Full Bands details, are particularly prized.
- **Value:** The value of Mercury Dimes can range from a few dollars for common, circulated varieties to tens of thousands for rare key dates in high grades.

The Mercury Silver Dime is celebrated for its beauty and the artistic quality of its design. Today, it remains a favorite among collectors for both its numismatic value and its symbolism of American ideals and freedoms.