925 Solid Sterling Silver 5g 2cm Heart Pendant

This came from a sterling silver necklace. It was badly tarnished and I had it cleaned. The necklace is stamped 925, but this pendant is not even though it is solid sterling silver. The pendant weighs 5 grams. It is 2cm wide and 2.5cm long. It is 2mm deep. The jump ring is 9mm wide.