Alma Mater
Alma Mater is literally the mother soul of the college/university. In the context of Columbia, Alma Mater almost always means the Daniel Chester French sculpture that graces the steps to Low Library.
It was a gift of Mrs. Robert Goelet and Robert Goelet Jr. in memory of Robert Goelet, Columbia College Class of 1860, and presented in 1903.
Alma Mater was originally intended to be guilt in gold, but never was. The bronze eventually oxidized and the statue was instead coated and sealed.
Urban rumor has it that back-up Alma Maters are kept at the ready should need arise. During the 60's and 70's, it seemed likely. According to this fable, one alum recalls hearing an explosion while in class in 1970, and finding Alma Mater skewed off her base later that day, though not fallen. Rumor has it that this was the work of the Weathermen. There is no known evidence in support of any of these claims.
An owl is hidden in the folds of Alma Mater's robes. According to legend, the first student of each College class to find the owl would graduate Valedictorian and marry a Barnard woman (back when Columbia College was still all-male.)
On the back of Alma Mater's chair you'll find the Columbia Crown and Columbia Seal lightly embossed in the metal.
Columbia's Alma Mater has a sister at the University of Havana. The Cuban Alma Mater was created in 1919 by Mario Korbel and inspired by Columbia's Alma Mater, while Korbel was residing in New York City. More recently, it served as somewhat uncanny validation for Bill O'Reilly's claim that Columbia is the "University of Havana North".
School Song
In the United States, an "Alma mater" is also the school song. Columbia University's is "Stand, Columbia", and the College's is "Sans Souci".