Hatton Garden: Behind the scenes of London's declining diamond district
But, squeezed by rising rents and falling profit margins, the street and the businesses that make it are both under threat.
Online jewellery shopping is rising in popularity, and savvier consumers are finding better deals elsewhere.
Meanwhile, developers are eyeing the street's prominent Central London position for both offices and luxury flats.
Business Insider went behind the scenes to find out what was going on.