Just spit balling, but it might be possible to flatten the platters out to recover some of the data, maybe even enough to piece together what was on there. The proper method for destruction is to wipe the drives, then shred them.
I figured, but I wanted to point it out because I'm so tired of seeing good SSDs get shredded or otherwise destroyed for "security".
Shredding was already a bit overkill for HDDs that were able to be properly wiped but at least there were some possible fringe cases. There's really no excuse for SSDs though
That I'm not sure, I know the premise is that data is read and written magnetically, which would lead me to believe there is some kind of ferrous metal in there somewhere, but I couldn't tell you the actual composition of the platters.
With tearing apart drives over the years, 3.5" always used aluminum platters, while the 2.5" ones used glass. (With greater data density and higher speeds however, this may have changed)