Cross enamel disc brooch, Bos (2008) Type 2.5.1.22 large, 8 fields outside, a circle in the middle
Literature:
J. M. Bos, Medieval brooches from the Dutch province of Friesland (Frisia). A regional perspective on the Wijnaldum brooches. Part II: Disc brooches. Palaeohistoria 49/50, 2007/2008, 709–793.
Egon Wamers, Die frühmittelalterlichen Lesefunde aus der Löhrstrasse (Baustelle Hilton II) in Mainz. Mainzer archäologische Schriften 1 (Mainz 1994).
In southern Lower Saxony, the situation with disc brooches seems to be "Westphalian". After only two years of intensive prospecting, around 30-40 brooches have been found in centrally located settlements (near the transport and trade routes) from the 9th to 12th century. The quantity also surprised us! 😄