Blue butterfly on marjoram

This is, I think, a chalkhill blue (would make sense), though I am not good at identifying the different blue butterflies.  It's feeding on marjoram (origanum vulgare) which grows all over the chalk hills round here.  It was by no means the only blue I saw this morning - in fact I sat on a hillside so alive with them it was hard to know which one should be picked out as a possible blipstar ;))  Aren't they beautiful?  Though I have to say I've noticed recently they have some unspeakable habits, grubby little things!!

Have a happy Tuesday evening  xx