and its source quarry in Hillsborough were identified by Duke University Comptroller Frank Clyde Brown and purchased by the university in 1925. Comptroller Brown, who oversaw the planning and construction of the Gothic buildings, wrote that Duke stone "is much warmer and softer in coloring than the Princeton, and it will look very much older and have a much more attractive antique effect."
Duke stone is a type of Carolina 'slate' or 'bluestone', a metamorphic phyllite rock, with both andesite and dacite mineral composition. Dacitic phyllite is a predominant type of rock found through the Carolina Slate Belt. Duke stone and the Carolina Slate Belt, like the greater Carolina Terrane, are thought to have formed in the Iapetus Ocean off the coast of Gondwana by a chain of volcanic islands known as 'Carolinia', starting around 650 million years ago.
The Carolina Slate Belt contains stone of both meta-volcanic and meta-sedimentary origin. The geological literature finds the pre-metamorphosis origin of Duke stone to …
中文名/译名
SAT EBRW 25%
740
SAT EBRW 75%
770
SAT Math 25th %
770
SAT Math 75th %
800
ACT Composite 25th %
34
ACT Composite 50th %
34
ACT Composite 75th %
35
介绍+详细信息
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