Similar examples are illustrated in this discussion of the Curonian animal style as manifested in brooches: http://etalpykla.lituanistikadb.lt/fedora/get/LT-LDB-0001:J.04~2000~1367162039681/DS.002.1.01.ARTIC Fig.12
"Daumen/Tumiany type"

"The Semigallians" (2005), pg 83 shows comparable examples dated 8th-9th century.

Baltic tribal areas established in around the fifth century in a broad area of barrow-culture territory, the Semigallians in Lithuania and eastern Latvia, the Curonians in western coastal Latvia and Lithuania.

In c. 1075 Adam of Bremen described the Curonians in his Gesta Hammaburgensis Ecclesiae Pontificum (Deeds of Bishops of the Hamburg Church) as famed pagan diviners:
"... gold is very plentiful there, the horses are of the best. All the houses are full of pagan soothsayers, diviners, and necromancers, who are even arrayed in a monastic habit. Oracular responses are sought there from all parts of the world, especially by Spaniards and Greeks." (Wikipedia article).

There is evidence for an active Scandinavian presence in the tenth and eleventh centuries (The Semigallians 2005, pg 154) and from the end of the eleventh century there were ever closer trading connections with the Rus'. There were also strong trade connections with Ugro-Finnic tribes of the Baltic, especially the Livs, from the eleventh to to thirteenth centuries, with openwork zoomorphic pendants being particularly distinctive.

There seems to be very extensive overlap in the styles of ornament between Curonians, Semigallians and neighbouring groups such as the Latgallians.