Was Jean Harlow's Hair naturally Blond?

Yes. She was a tow-head as a child and it darkened into a honey-blonde as she got older. Her platinum look was achieved through a pretty torturous process involving ammonia, Clorox bleach, and Lux soap flakes. She had to have fans blowing on her to cut down on the burning sensation. It also ruined her hair, so that she wore wigs often on screen.