Table schema:
CREATE TABLE table_15624586_2 (indigenous_mining_production_2006 VARCHAR, _percentage_of_world_demand VARCHAR)

Question: What is the  indigenous mining production of the country that uses 3.4% of the world demand?
SQL: SELECT indigenous_mining_production_2006 FROM table_15624586_2 WHERE _percentage_of_world_demand = "3.4%"