Diamonds!

Richman, Barak D., “How Communities Create Economic Advantage: Jewish Diamond Merchants in New York” (March 2005). Duke Law School Legal Studies Research Paper No. 65; Harvard Law and Economics Discussion Paper No. 384. http://ssrn.com/abstract=349040

This fascinating article explores how the diamond merchant market in New York has maintained a competitive advantage over other markets because of various values held by and enforced by the community.