It was the natives who named Dragonstone, the Valyrians agreed out of convenience.
There's a tale, all the children know of it, the tale of the lady of dragonstone.
The widows call her a witch, the boys say she is a whore who sleeps with beasts, the girls say she's one of the children but everyone knows she's the lady of dragonstone. Her body is deep within the island, fused with the magic of the realm, the kind that keeps the wildings out.
She wants the rubies back, she wants her crown back.