1875, The famous 20 k. with INVERTED CENTER, used with part strike of Jarmolintsy 20. Jan. 188(?) c.d.s., superb. The most beautiful of the 3 copies known to exist. (Mi.€75,000,- Sc. 30 b: $75,000,-; Russian cat. (2010): €200,000,- Mikulski certificate.)