I grew up in northern Michigan during the 50’s and 60’s....one of my neighbor friend’s father had a grinding wheel and polisher in his basement and he used to make ornaments and things out of Petoskey stones................Pretty cool stuff.
My mom had one, too! I just go to a cave gift shop and get them there. Can’t take the noise. The best cave I was ever at was Crystal Cave in Springfield, MO. Privately owned.