turquoise vs cobalt blue

turquoise and cobalt blue both are nouns.

Word	Noun	Adjective	Verb	Adverb
turquoise	Yes	No	No	No
cobalt blue	Yes	No	No	No

As nouns, turquoise and cobalt blue are synonyms defined as:

Other synonyms of turquoise include aqua, aquamarine, greenish blue, peacock blue.

turquoise (noun)	cobalt blue (noun)
a shade of blue tinged with green	a shade of blue tinged with green
a blue to grey green mineral consisting of copper aluminum phosphate	greenish-blue pigment consisting essentially of cobalt oxide and alumina