Got the seaweed short.
Don't know what to think about it...
I guess this greenish color will be pretty weird with the purple polo
Anyway... here is a picture comparing AO11 grey sage
/ USO11 anthracite
(and a second one with blue/purple stripes).
Seaweed is actually a darker "grey sage", as stated above (but anywhere near anthracite as I could also read there)