Sterling silver (.925) proof quality, approximately 20 grams. Manufactured in September 1978, never removed from the capsule since purchase. ※ The 500-yen coin is for size comparison and is not included. The original box, etc., has been disposed of. ※ I remember it cost over 8,000 yen at the time of purchase. ※ The certificate of authenticity has stains as shown in the photo. Country...Japan