Archaeologists have uncovered a Viking Age grave in Skaun, Norway that most likely contained the remains of a warrior. The person died in circa 950 AD and was buried with their weapons, which included a well preserved sword and shield boss.
The wooden part of the shield had decayed and disappeared in antiquity but the metal boss survived. It contained a strike mark on its surface, most likely delivered by an axe or sword, indicating that it had been used in combat. More surprisingly, the shield boss also contained a number of Islamic coins, which had been hidden inside a leather bag.
According to archaeologist Ingrid Ystgaard, the coins may indicate ‘that this person visited the eastern part of the Viking world, possibly a town such as Holmgard in what today is Russia‘.
Source: NRK
Surely not too ‘surprising’ to find Islamic coinage as they traded/sold slaves to the occupants of southern Spain.
Surprising to find it in the shield boss, it’s a not a typically hiding pace for such items. But you’re right, Islamic coinage is not that unusual from Viking Age contexts.
Sea wasn’t the only route to Islamic connections. The Vikings traded overland and rivers right down into Istabul. There is carved Viking graffitti inside Hagia Sofia.