It turns out the streets of New York really are paved with gold - as long as you don't mind searching for it on your hands and knees.

Raffi Stepanian, a self-styled urban prospector, has discovered enough tiny jewellery fragments hidden in the sidewalks of the city's Diamond District to make a living.

Using nothing more than a Styrofoam cup, tweezers and a butter knife, he collects hundreds of dollars worth of gold, diamonds and rubies each week.