Common Grass-blue

The upper side of the wings of the Common Grass-blue is coloured a delicate mauve-blue in the males, sometimes tending to slightly more purple or blue, with a narrow brown margin. The females are a mid-blue to purple with broader mid-brown margins. Some females are nearly all brown; others are similar in colour to the males. Both sexes have a pale grey-white fringe of scales on the outer margins of the wings.
The underside of the wings is a pale colour, varying from the softest grey, through to a very pale fawn-brown. Rows of spots and chevrons of a somewhat darker brown, with obscure white surrounds, mark this background.