Generally speaking, they should work fine. Mohair is very warm, so that's not an issue, and also is reputed to keep you comfortably cool when it's warm. Durability also is not a problem -- those Angora goats were raised in tough, tough country, and won't have wimpy wool. Keep in mind, however, why merino wool socks have become so popular in recent years. It's because merino wool, along with the attributes of warmth, softness and so on, has tiny pockets in the wool fibers that absorb huge amounts of moisture. This helps keep your feet dry even when you're sweating heavily. Mohair sock makers claim similar qualities, but whether you'd gain anything is hard to say.
So give them a try! You won't be out much, and you might find you like them better than the wool socks you're wearing now.