/usr/share/gmt/cpt/copper.cpt is in gmt-common 5.3.1+dfsg-2.
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1 2 3 4 5 6 7 8 9 | # $Id: copper.cpt 16562 2016-06-18 04:04:08Z pwessel $
#
# Simulates the COPPER colormap in MATLAB
#----------------------------------------------------------
# COLOR_MODEL = RGB
#----------------------------------------------------------
0 black 0.796875 255/159/102
0.796875 255/159/102 1 255/200/128
#----------------------------------------------------------
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