This brooch is based on a Viking Age find from Eskelhem on Gotland. The pin is very robust and is excellent for holding larger cloaks in place.
The original was made of bronze and is now at the Historical Museum in Stockholm, which can be seen here: https://samlingar.shm.se/object/9F6701BB-1769-45D5-BE62-2817D66D5034
Made of bronze.