This is not a Niemberg fibula, but rather an Elbe Germanic crossbow fibula without its own type designation from the late imperial period, level RKZ C3. Jan Bemmann has listed some comparative examples from the Harz region and defines the fibula type as follows: "Characteristic of this Elbe Germanic fibula type is a long spiral, a head folded over to form a flap, an outline tapering from the head to the tip of the foot, a long, open needle holder emerging from the side of the foot. The bow and foot are faceted and can have transverse grooves that frame edge notches." See here: Open link: www.academia.edu