This Damascus “coin” was made by master bladesmith Mamoru Narasada from Nagano, Japan.
The steel is a variation of sanmai (3 piece) Damascus with a core of SKD11 and sheathed with high-nickle SUS304 Damascus plates. This type of steel is common in custom cutlery.
Approximate measurements: OD- 20mm; ID- 4.5mm; Thickness- 2.7mm; Weight- 6g
(Due to the hand made nature of these pieces, each is slightly different in size, weight and appearance.)