Iron buckle and plate with organic remains

Iron buckle and plate, maximum width of loop 3.75cm, length including plate 4.4cm. Loop and plate corroded together, but loop oval with simple tongue, plate rectangular folded over loop and presumably riveted, but how many rivets did not show up either on external examination or X-ray. The back of the plate is covered by a single layer of mineralized textile, a plain weave, perhaps checked, count 12 x 12 approx. per cm. It looks like a linen shirt, ergo probably from a man's grave. Traces of another material, perhaps tooled leather, at top of plate and behind loop. An old label once stuck on centre back of plate survives just in outline, 1.5 x 8 cm.Bifrons or Sarre.