This coin is a 2019 "War in the Pacific" Quarter (featuring the Guam design) that has suffered from extreme heat damage. It is not a mint error.
Here is why it looks this way:
The Bubbled Surface: Modern quarters are made of a "clad" compositionโa pure copper core sandwiched between two outer layers of nickel-copper. When these coins are exposed to extreme heat (like a house fire, a bonfire, or a blowtorch), the layers expand at different rates. Gas trapped inside or the expansion of the inner core causes the softened metal skin to bubble up.
"Mushy" Details: The details on Washingtonโs face and the soldiers on the reverse look melted or soft. This is a classic sign that the metal reached a temperature high enough to soften it, causing the sharp design elements to flow and lose their definition.
Porous/Rough Texture: The pitting and roughness occur as the metal cools down after being overheated, leaving behind a scarred surface.
Is it a Mint Error?
No. It is important to distinguish this from valuable errors:
Grease Errors: Sometimes grease gets into the die at the mint, but that results in smooth, missing details, not a bubbly or pitted texture.
Planchet Errors: While metal defects exist, they do not cover the entire coin in bubbles like this. This "melted" look is distinctive to fire damage.