The good thing about mount rushmore is that granite erodes very slowly so this monument is going to loom above the black hills for a long long time.
Why was mount rushmore made of granite.
The sculpture of four famous presidents george washington thomas jefferson theodore roosevelt and abraham lincoln was carved into the granite rock face over many decades.
In fact granite erodes roughly 1 inch every 10 000 years which is great news for this piece of american history.
After the honeycombing the workers smoothed the surface of the faces with a hand facer or bumper tool.
Sculptor gutzon borglum created the sculpture s design and oversaw the project s execution from 1927 to 1941 with the help of his son lincoln borglum.
450 000 tons of rock was removed during the construction.
In this final step the bumper tool would even up the granite creating a surface as smooth as a sidewalk.
Mount rushmore includes the faces of american presidents george washington thomas jefferson abraham lincoln and theodore roosevelt.
The granite is a very hard rock and the mica schist is much softer.
The presidential trail a walking trail and boardwalk starts at grandview terrace and travels through the forests to the sculptor s studio now a museum with information about the construction of the monument and the tools used by.
What you see today.
Mount rushmore national memorial is centered on a colossal sculpture carved into the granite face of mount rushmore in the black hills in keystone south dakota sculptor gutzon borglum created the sculpture s design and oversaw the project s execution from 1927 to 1941 with the help of his son lincoln borglum.
Another piece of honeycombed granite was sent down ready for the next visitor looking for a special souvenir from mount rushmore.
The granite was once molten rock and the mica schist was formed as a result of the heat and pressure exerted by the molten rock.
The sculpture features the 60 foot 18 m heads of presidents george washington.
The two stories of the rocks at mount rushmore the origin of the rocks and the creation of the current topography are as different as the rock types found here at the mountain.
How mount rushmore became mount rushmore the south dakota landmark has drawn criticism over the land it occupies the main sculptor behind it and the legacies of the men it memorializes.
The granite remains from the construction of mount rushmore are still visible below the heads of the presidents.
Mount rushmore was carved from a mountain that was made of exposed granite.