That's the Pan American Exposition in Buffalo where President McKinley was assassinated. I guess maybe he should have carried one of those.
Yeah, I know, a necrothread, but worthy of posting this one. I think I just found the "Holy Grail" of encased coins . . . . . . Z
No leg pulling, but it isn't mine either. Ran across it on TokenCatalog. If it were mine, it would have MUCH better photos . . . . . but a boy can dream, cain't he? (TC-562447) Now I'm wondering what the surround encasement is made of. Looks like similar toning and color . . . . . Z
Not quite as impressive or nearly in the same category as @ZoidMeister's masterpiece, but here's my 'encased' cent from my grandmother. She's the one who got me into coins 56 years ago.
If you're ever in Tennessee, most coin shops have the irradiated dimes. The Oak Ridge atomic plant is in Tennessee. Zoid -- I saw one of those about 5 years ago at a regional coin show. Can't recall the asking price, but way out of my reach. I collect Encased Cents as a side line to my main collection. Here's a few of my better ones.