Sorry â€“ not the best off photos.
These metallic dull green bees are present in large numbers on a south facing brick wall. They seem to be nesting within holes in the soft mortar of the wall.
No interactions present.
Lat/Lng: 52.725425502573, 0.30971199274063
OS grid ref: TF560166
Wall of building next to a sown wildflower meadow about 10 years old