Source: Superman's Pal, Jimmy Olsen #21 (1957)
Anyway, off we go on a pirate adventure, and for some insane reason, Olsen's ancestor has a green beard (hence the name), so of course it has to be made of kryptonite or something, right? That's what allows him to push Clark off the gang plank, right? Well, time will tell.
And the green beard wasn't, in any way, connected to kryptonite! It is entirely connected, however, to my bitter disappointment! Come on now!