Confidence: It's likely to be this, but I can't be certain.
Notes: The fly is less blue than the individual identified as C. vicina in my post: “Bluish fly” (to iSpot 02/03/2013). This individual a dull blue version of Calliphora vomitoria perhaps? ..,but does a striped underside match (lower image in the composite)? The basicosta is possibly orange in that rather poorly focussed image .. or yellow in Image 1 (??) but not obviously either in the upper images of the composite.