If the mystery astronaut was Harrison Schmitt then he would have been an expert in these kinds of rocks, although all the Apollo astronauts had geological training, IIRC.
If he was talking to a class of half of a group of 28, so about 14 pupils, somebody has to have recognised the significance of a goddamn Apollo astronaut. Have you contacted any of your classmates, either you’re misremembering something about the day or someody is still telling random strangers about the day #####, an actual Apollo astronaut, came to talk to them.
I’m about 5 years older than you and I know at the ages you present that would have been the highlight of my entire school career.
The curation of Antarctic meteorites is taken as seriously as those of Apollo return specimens, so it seems as improbable that a “naked” hand specimen of an Antarctic lunar meteorite would be casually passed around as would an Apollo specimen. And the first non-Antarctic, privately owned lunar meteorite wasn’t identified until 1991, and it was only 19 grams (somewhere around the size of a walnut.) It wasn’t until 1997 when the next non-Antarctic lunar meteorite was found, during the Sahara desert meteorite gold-rush. (It is a similar story with Martian meteorites–very few until cheap Sahara finds brought sample prices down from tens of thousands of dollars a gram to mere hundreds of dollars per gram.)
(ETA I see that there was a fairly large (more than 2 kilos) lunar find this year, and slices of it are available at the very low price of approx. $200 per gram.)
Two people I can think of that I “know” (in the “have all been contributing members in the same mailing list for a number of years” sense) who are both approachable and very knowledgeable are Ron Baalke and Randy Korotev. If you could contact either of them, they would have as good a chance of any of knowing where lunar samples were tagging along with Apollo astronauts in the 1990s.
I will cheerfully concede that I quite likely got the samples mixed up.
Unfortunately, I haven’t spoken to any of my former classmates from that school since I was about 12. One sent me a message over one of those ‘find your old school friends’ sites about 10 years back, which I replied to and heard nothing else, but that’s been it. I didn’t live in the same village as the rest of the school (it was near my parents’ work), and I went to a different secondary school from everyone else.
I could possibly get in touch with a classmate’s parents, as they ran a pottery studio at which I took classes, which is still going, but I’d be a little uncomfortable doing that, if I’m honest. She was younger than me, and I wouldn’t expect that she would remember any more than me anyway. It was presented to us as nothing very important, and we treated it as such.
I realise how weird it all sounds, but honestly, it was a strange little school, run pretty much wholly according to the head’s whims. I can see her signing up for something like that because it sounded kind of interesting, but not really thinking it was a big deal. She used to tell us stuff she’d been told by ‘psychics’ she’d met at fairs. Nice woman, but a bit odd.
I’ve tried messaging that NASA Facebook group, thanks for the suggestion! I’ll let you know if they get back to me!
FYI, I’ve reached out to a friend of mine who is an Apollo historian at the Smithsonian’s National Air and Space Museum, where I used to work. I’ll get back if he replies.
ETA: my office at NASM was about 100 feet from one of the only lunar samples anywhere in the world that is available for the public to actually touch.
The NASA Astronaut Appearances Facebook group did get back to me, but their database only goes back to 2000, and they couldn’t suggest anywhere that might have any info from before that.