Cool names
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Cool names
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I think they used the name of Blackrock from this..
"The Rupes Nigra ("Black Rock"), a phantom island, was believed to be a black rock located at the North Magnetic Pole or at the geographic North Pole itself. Described by Gerardus Mercator as 33 French miles in size, it provided a supposed explanation for why all compasses point to this location. The idea came from a lost work titled Inventio Fortunata, and the island featured on maps from the sixteenth and seventeenth centuries, including those of Mercator and his successors. Mercator described the island in a 1577 letter to John Dee"
The theory of it being from the guy standing right beside him makes the most sense.