Iron-Age copper-alloy inlaid horse harness fitting?

Card 1:Only 18inches wide. One diamond shaped bronze ornament, 1 1/2 X 1 1/4 inches, ivory bosses at 4 angles, each pierced in centre with dot of lapis lazuli, 4 bronze attachments loops behind. Substantially made and in perfect condition. 2 lapis lazuli now missing.Card 2: Lozenge-shaped bronze mount, 4 x 2.8 cm. At the angles are cast cells containing cabochon settings of white paste (or probably shell, but this is not v. likely) each with a small disc of blue glass or lapis lazuli at the top (two now missing). The cells are linked by short, semi-circular sectioned bars, with plain double mouldings at either end. At the back, behind the cells are pierced loops to allow attachment to the belt or dress.