Here we go again....

[Dan/Panther]

Aqua, or Turquiose.
The auction says Aqua, but it looks Turquoise to me.
D/P

[Phonesrfun]

I agree and vote for turquoise, although the cords look more blue than the shell and handset.

[foots]

I say its aqua, with a lot of yellowing.

[LarryInMichigan]

I used to see alot of WE phones in that color back in my youth 30-35 years ago, and they were usually yellowed back then as well.  When I was a teenager, I had an early TT Trimline in that color.  Some parts of the shell were bluer and others were greener.  I suspect that the pigments used were very sensitive to light.

Larry

[McHeath]

I'd guess aqua with a lot of exposure to fading or smoke.  My aqua 1500 was about that color, cords and all, when I got it. 

[Dennis Markham]

The answer lies within the cavity of the handset and the housing.  The handset cord especially looks aqua.  If we could pick up the handset and look below that might tell the answer as well.