I saw 2 of these out on a walk today Cuil Bay, North Argyll
Any ideas? Never seen them before are they unusual or have I just not looked hard enough before?
These are green hairstreak butterflies, Callophrys rubi
They are charming little creatures. I am glad you feel rewarded for looking harder this time. Keep looking, and you stand a chance of noticing some of the other marvellous butterfly-gems of your countryside. ...Which may include the purple hairstreak, which is another superficially-drabish butterfly with a reward for the observant - the brilliant flash of metallic purple on part of the upperside.
See more British hairstreaks here
If you look closely at your photos, you'll I notice the white spots on the underside of the hind wings. That puts it in the aberration inferopunctata (shown further down that page).
So my full ID is Callophrys rubi ab. inferopunctata.
Thanks so much, will look out for more of them, posted another sighting tonight :)
What is interesting is the green is not a pigment just like blue in butterflies and bird feathers its down to refraction, like oil on water