Amber is one of the main sources of income in the small city of San Cristobal de las Casas in the southern state of Chiapas in Mexico. It is also one of the lesser known precious stones. Just by walking through the city, it is clear how many people rely on amber to make a living. However, it is becoming increasingly difficult to make a sustainable living from the amber trade, a fossilized resin which takes millions of years to develop.