These are from West Yorkshire Spinners Cocktail Collection of socks.
They are called Blue Lagoon and are in shades of lblue and sea green. They are made from Blue Faced Leicester wool with a small addition of lycra and elastane to give stretch. Each pair is unique and they come in two sizes. Small: UK 3 - 5 ( US 5 - 7) and Medium UK 6 -8 (US 8 - 10).
They are taller than an ankle sock, I think boot sock would describe them best!
Please click on the thumbnails to enlarge the views