I’ve found the F2 and F3 ones but I can’t find it for F1. I’ve found 3 chests in F1, each containing a different gemstone, but not the collection chest.
If anyone knows, I’d be appreciative to know, thanks!
EDIT:
Never mind, I found it! I don’t know how I missed it the first time. It’s just to the left of the exit that leads to F2, right after you beat the Specter boss.