The Half Dollar
50 cents
Today's half dollar is a larger version of the dime and quarter sandwich: copper-nickel outer layers bonded to a pure copper core, with the copper stripe showing on the edge. Its metal story is the most complicated of the clad coins. Until 1964 it was 90% silver. When silver prices rose in 1965, the dime and quarter went straight to copper-nickel, but the half dollar kept some silver: from 1965 to 1970 it was a silver sandwich with 40% silver overall. Only in 1971 did it switch to copper-nickel clad. The Kennedy half was heavily saved and hoarded from the start, so it has seen little everyday circulation.
Composition & Tolerances
| Variant | Standard Clad Half 1971–today | Historic Silver Half 1873–1964 | Historic 40% Silver Clad Half 1965–1970 | Counterfeit 1921-D Walker Fakes Struck counterfeits from Asia | Proposed 80/20 Clad Half Mint recommendation, not law‡ |
|---|---|---|---|---|---|
| Copper | 91.67% | 10% | 60%‖ | Not documented§ | Core plus skin‡ |
| Nickel | 8.33% | — | — | Not documented§ | Skin only, leaner than today‡ |
| Silver | — | 90% | 40%‖ | Genuine coin is 90%§ | — |
| Silver content | — | 0.3617 troy oz | 0.1479 troy oz | Genuine coin: 0.3617 troy oz | — |
| Structure | Cupronickel skins over a copper core | Solid silver alloy | 80% silver skins over a 21% silver, 79% copper core | Metal not documented§ | 80/20 cupronickel skins over a copper core |
| Target weight | 11.340 g | 12.50 g (192.9 grains) | 11.50 g | Genuine coin: 12.50 g§ | Same as today‡ |
| Weight tolerance | Not published* | ±1.5 grains† (about ±0.097 g) | Not published | None (made to no spec) | Not yet set |
| Composition tolerance | Not published | Not published | Not published | None | Not yet set |
| Diameter | 30.61 mm | 30.6 mm | 30.6 mm | Copied size | Same as today‡ |
| Thickness | 2.15 mm* | Not confirmed | Not confirmed | Not documented | Same as today‡ |
| Edge | Reeded, 150 reeds | Reeded | Reeded | Reeded (copied) | Same as today‡ |
| Magnetic? | No | No | No | Test it: a genuine coin is not magnetic | No (copper-nickel skin) |
| Specific gravity | 8.92¶ | 10.34¶ | 9.53¶ | Test it: genuine is 10.34¶ | Same as today‡ |
| Conductivity | Skin 5.5%, core 100% (of copper) | Not published | Not published | Not documented | Matches today‡ |
| How to spot it | Copper stripe on the edge; dated 1971 or later | Dated 1964 or earlier | Dated 1965–1970 | Weak strike, a lint mark in the right obverse field, fuzzy stars and rim lettering, and the same abrasions repeated on every fake | Not yet authorized |
Footnotes
Clad Half: * The Mint sets its tolerance on clad strip thickness for dimes, quarters and half dollars (±0.0015 in, 0.038 mm); a finished-coin weight tolerance is not published. ¶ Specific gravity values are commonly cited collector figures. Conductivity is a percent of pure copper (IACS).
Silver Half: † Legal tolerance: 1.5 grains on 192.9 grains (Newman Numismatic Portal). Earlier silver halves: 206.25 grains (13.36 g) before 1853; 192 grains (12.44 g) 1853–73, marked with arrows at the date (and rays on the reverse in 1853).
40% Silver Clad Half: ‖ Outer layers 80% silver, 20% copper; core 21% silver, 79% copper; 40% silver overall. The 1970-D was sold only in mint sets (2.1 million made) and is the series' key date.
1921-D Walker Fakes: § Genuine 1921-D mintage is 208,000, the lowest of the Walking Liberty series. NGC describes these fakes as struck in Asia and artificially toned, with abrasions copied from a genuine coin. Their metal is not documented, so compare weight, magnetism and specific gravity with the genuine figures.
80/20 Clad Half: ‡ The Mint's seamless 80/20 option (2022 Biennial Report) keeps today's weight, size and signature; it needs approval from Congress.
Sources
- U.S. Mint, Coin Specifications: https://usmint.gov/learn/coin-specifications
- Wikipedia, Kennedy half dollar: https://en.wikipedia.org/wiki/Kennedy_half_dollar
- Stack's Bowers, Liberty Seated Half Dollar, Arrows and Rays: https://stacksbowers.com/coin-resource-center/us-coins/half-dollars/liberty-seated-half-dollar/liberty-seated-half-dollar-type-2-arrow-and-rays/
- Newman Numismatic Portal, Tolerance: https://nnp.library.wustl.edu/concern/dictionaries/dict516903
- NGC, Counterfeit Detection: 1921-D Half Dollar: https://www.ngccoin.com/news/article/2920/1921-d-half-dollar/
- CoinTalk, Coin Specific Gravity (collector chart): https://www.cointalk.com/goto/post?id=2132275
- USPTO, Coinage cladding alloy patent (C71300 conductivity): https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/10513768
- U.S. Mint 2022 Biennial Report to Congress: https://usmint.gov/wordpress/wp-content/uploads/2023/04/2022-USM-Biennial-Report_P5_FINAL.pdf