What color is Blueprint, Apartment House, Rue Heine, Plan des Etages 1e et 2e, 1925 ?

Source Crayola® CSS3 CSS4
#567fa5
 
#5d76cb
indigo
#4682b4
steel blue
#4682b4
steelblue
#80a0b7
 
#979aaa
manatee
#778899
light slate grey
#778899
lightslategrey