Table schema:
CREATE TABLE table_name_13 (name_of_the_stone__sila_ VARCHAR, name_of_the_state_where_found_in_india VARCHAR)

Question: What is the name of the stone found in Andhra Pradesh, India?
SQL: SELECT name_of_the_stone__sila_ FROM table_name_13 WHERE name_of_the_state_where_found_in_india = "andhra pradesh"