Editing Openai/6928c8bd-a418-800a-b930-04098eeef67a (section)

== gpt-5-1 ==
=== User: When and what coins did the Philadelphia Mint put a mint mark on coins with a “P?” ===
When and what coins did the Philadelphia Mint put a mint mark on coins with a “P?”

=== Assistant: Here’s the complete, accurate timeline of when the Philadelphia Mint used the “P” mint mark, and on which coins. ===
Here’s the complete, accurate timeline of when the Philadelphia Mint used the “P” mint mark, and on which coins.
Philadelphia normally struck U.S. coins without a mint mark, so anytime you see a “P”, it’s a special case.

=== ✅ Full History of the “P” Mint Mark ===

!https://www\.fcmint\.com/pub/media/catalog/product/cache/afad95d7734d2fa6d0a8ba78597182b7/r/a/rare\_p\_mint\_marks\_wallet\_1200\.jpg<ref>{{cite web|title=https://www\.fcmint\.com/pub/media/catalog/product/cache/afad95d7734d2fa6d0a8ba78597182b7/r/a/rare\_p\_mint\_marks\_wallet\_1200\.jpg|url=https://www.fcmint.com/pub/media/catalog/product/cache/afad95d7734d2fa6d0a8ba78597182b7/r/a/rare_p_mint_marks_wallet_1200.jpg|publisher=fcmint.com|access-date=2025-11-28}}</ref>
!https://i\.usacoinbook\.com/us\-coins/1980\-lincoln\-memorial\-cent\.jpg<ref>{{cite web|title=https://i\.usacoinbook\.com/us\-coins/1980\-lincoln\-memorial\-cent\.jpg|url=https://images.openai.com/static-rsc-1/g-6TcHZ1chb5gB_B5iIphq340nrmr3U5PWJRmFWBWLijNtF6JZBXkbJOeYmrRcNHYUY7sEtQjGeR8XmiGPEO5fxda9VsR2x3bdlVDgAZZzpUp4i-DnCaFPkuUZsCYYkpBwtONRFH8G3hF42qSErq2A|publisher=images.openai.com|access-date=2025-11-28}}</ref>
!https://profilecoins\.com/cdn/shop/products/442R\.AC\-rev\.jpg?v=1697045122&width=2048<ref>{{cite web|title=https://profilecoins\.com/cdn/shop/products/442R\.AC\-rev\.jpg?v=1697045122&width=2048|url=https://images.openai.com/static-rsc-1/OGlkIyfBvyAH039pSA_llxV3yMAzqqWvCHkInZHwJUy_pHiBcKqGNH7iUZgD_UHTibKduP8o68rgGk1shFJGZ3baGM4BdkXpAl3sjuPMTo0uu_UjCcbuQdbYeDyb3bwyg8LQ7pknSTsqyUQuUI0Dfw|publisher=images.openai.com|access-date=2025-11-28}}</ref>
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=== 🕰️ 1. WWII Silver Nickels (First Ever “P”) — 1942–1945 ===

Coins: Jefferson “Wartime” Nickels
Mint mark location: Large letter above Monticello
* 1942 (silver type only)
* 1943
* 1944
* 1945

This was the first time in U.S. history Philadelphia used a mint mark.
Reason: to identify the special 35% silver alloy during wartime.

=== 🕰️ 2. Susan B. Anthony Dollars — Since 1979 ===

Coins: SBA Dollars (1979–1981, 1999)
Mint mark location: Left of the portrait

Starting in 1979, Philadelphia put its “P” on the new dollar coin because the design needed clear mint identification.

=== 🕰️ 3. All Denominations Except Cents — Since 1980 ===

Coins:
* Nickel (Jefferson) – P appears starting 1980
* Dime (Roosevelt) – P appears starting 1980
* Quarter (Washington) – P appears starting 1980
* Half Dollar (Kennedy) – P appears starting 1980
* Dollar Coins (SBA, Sacagawea, Presidential, Native American, Innovation dollars) – always include P when struck in Philly

Before 1980, Philadelphia put no mint mark on these coins.

=== 🕰️ 4. A One-Year Special: The Lincoln Cent “P” — 2017 Only ===

Coins: Lincoln Shield Cent
Mint mark location: Standard position below the date

In 2017, for the U.S. Mint’s 225th Anniversary, Philadelphia added a “P” to cents for the first and only year ever.
* 2017 cents are the only Lincoln cents in history with a P mint mark.

=== 🕰️ Summary Table ===

| Denomination                   | First Year With “P” | Notes                            |
| ------------------------------ | ------------------- | -------------------------------- |
| Nickel (WWII silver)           | 1942–45 only        | Special war alloy                |
| Dollar coins                   | 1979                | SBA, then all later dollars      |
| All regular coins except cents | 1980                | Nickels, dimes, quarters, halves |
| Lincoln cent                   | 2017 only           | Anniversary issue                |

If you want, I can also show:
* Which coins should never have a P (so you can spot errors)
* Values of P-mint coins you have
* Photos of the mint mark positions on each denomination