The gemstone

About her neck
Had been plucked
From the skull
Of an empress
Disturbing her sleep
Of ages
She’d once kept
Entire villages in cages
So when it glimmered
And pulsed with runic
Hue she’d remove it
Fearing its malefic power
One day she misplaced
It and a giant rat in
Her apartment appeared
Wearing it but it didn’t faze
Her, he could only dodge
Her broom a tiny bit better