[QUOTE=
The OP was asking specifically about ankle socks. I don't have a source for 100% wool ankle socks, but besides the nylon blend socks mentioned above, I will mention Thermohair. These are 75% Mohair and 25% nylon. They do make ankle socks. I don't know about the ankle socks, but the crew/calf length socks are thick and very warm. They're made in Canada and prized by people in the north. The thing I've noticed is that they tend to be very slippery. I don't know if that's the Mohair or the nylon, but my feet slide around less inside the boot with wool socks.[/QUOTE]
Just a note of clarification. Considering the socks I have cycled with, the ankle socks tended to be thinner than the crew. For summer, I want a thin merino wool sock. If a crew sock fits the bill, that would be fine, I just haven't seen that. Yet anyway.