Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_34 (us__1912_ VARCHAR, us__2013_ VARCHAR)
### Question:
What was the U.S birthstone in 1912 when in 2013 the birthstone was amethyst?
### Answer:
SELECT us__1912_ FROM table_name_34 WHERE us__2013_ = "amethyst"