Japan. Rare Silver Test Plate for Coinage Punches

Mid-1800s. Uniface. 3" by 5" dimensions, 20 mm thickness. Decidedly rare; we've heard of only one other, that in gold. Many of the symbols shown here are found on the Oban and Koban gold coin series of the mid-1800s. A great and rare prize that should set Japanese coinage specialists afire with bidding activity.