which materials were used to built the aforementioned monument?
It is made of marble, granite, and bluestone gneiss.
Washington Monument
Located almost due east of the Reflecting Pool and the Lincoln Memorial, the monument, made of marble, granite, and bluestone gneiss, is both the world's tallest predominantly stone structure and the world's tallest obelisk, standing tall according to the U.S. National Geodetic Survey (measured 2013–14) or tall according to the National Park Service (measured 1884). 
where did the granite for the washington monument come from UNANSWERABLE where is this monument located? It is located on the National Mall in Washington, D.C.. when was this monument built? 1888 for what purpose it was built? It was built to commemorate George Washington. who is this person you just mentioned? He was an American political leader, military general, statesman, and Founding Father who served as the first president of the United States from 1789 to 1797. where was he born? Westmoreland County, Virginia.
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Washington Monument [SEP] Introduction
The Washington Monument is an obelisk on the National Mall in Washington, D.C., built to commemorate George Washington, once commander-in-chief of the Continental Army (1775–1784) in the American Revolutionary War and the first President of the United States (1789–1797). Located almost due east of the Reflecting Pool and the Lincoln Memorial, the monument, made of marble, granite, and bluestone gneiss, is both the world's tallest predominantly stone structure and the world's tallest obelisk, standing tall according to the U.S. National Geodetic Survey (measured 2013–14) or tall according to the National Park Service (measured 1884). It is the tallest monumental column in the world if all are measured above their pedestrian entrances.