The youngest millionaire in the US made his fortune by buying stones.

Core summary: American little boy Ferrari Gray began "entrepreneurship" to support his family at the age of 6. He first picked up some stones on the street, painted them with colors and used them as "paperweights" for door-to-door sales. Then he started to establish his own chamber of commerce and engaged in the sales business of cookies and gift cards. By the time he was 14, Gray had already turned from a penniless poor boy to the youngest millionaire in the United States.