Older pieces that started out regular old blue can fade/yellow to many different
looking shades. Look underneath to get a sense of how old the tile is.
Sky blue came is one set 20 years ago... Unless you have found other elements
from that set in the bin you are looking through I doubt that's what it is.
left most is definitely medium blue. right most is definitely maersk blue.
2nd to right is definitely medium azure. what is the other one?
the colors come across terrible in the picture...but even just looking at the
palette of known colors, sky blue is the only one that fits, right?
Looks more like Maersk Blue to me. Sky Blue is really, really similar to Medium
Azure.
Reason I think it's Maersk Blue is because it looks darker than the Medium
Azure tile, where as Sky Blue is perhaps ever so slightly lighter. Maersk Blue
is known to have changed over the years.
Maersk Blue tiles from
USA, Pennsylvania
Sweden, Örebro
Israel, Mehoz Tel Aviv
Portugal