Like all collecting, my interest in bullion is by theme. I am a writer. I learned to fly. I value the philosophers who advanced individualism. It is personal (even though they are bullion). Among them are ...
ASE,S another good choice, as they are still monetized and have actual Value be it only a dollar but still
A long time ago, Boy Scouts working on a merit badge were told to "brighten" their cents with a pencil eraser. In the 1980s, third party grading took off and took hold. But the fact is that not much is new under the sun. Back in the 1970s, roll collecting was a fad or trend. Imagine if you had a roll of uncirculated 1877 Indianhead Cents or 1916-D Mercury Dimes that had been set aside all these years... So, some investor-collectors looked for recent date, low mintage coins, uncirculated in wrapped rolls. Mostly, they sold them to each other. They still do. Put "1955-D Quarter Dollar uncirculated roll" in your search engine. As John Higley said, "Value me as you choose."
For just trading among friends, when your kids maybe an eraser would Be ok but if you ever submitted that for grading would probably Come back as non grad able, with remarks.