So yeah it’s pretty obvious that Rose wasn’t the one who shattered Pink Diamond but who else could Blue Diamond choose that had a sword?
You know what other gem had a sword

And you know that Gemsona Maker which makes THIS when fusing a pearl, amethyst, garnet and rose quartz

(Forgive how they look I just did this quickly)
And you know how ROSE IS PART OF THE FUSION
AND YOU KNOW THE WHOLE ‘ONLY DIAMONDS CAN SHATTER OTHER DIAMONDS’ THING