Which month in 2013 did the U.S. use the ruby birthstone?
CREATE TABLE table_name_76 (month VARCHAR, us__2013_ VARCHAR)
SELECT month FROM table_name_76 WHERE us__2013_ = "ruby"
### Context: CREATE TABLE table_name_76 (month VARCHAR, us__2013_ VARCHAR) ### Question: Which month in 2013 did the U.S. use the ruby birthstone? ### Answer: SELECT month FROM table_name_76 WHERE us__2013_ = "ruby"