cover 1884 (28 Mar.) envelope registered to Halifax, Nova Scotia, bearing 1882 CA 10c. mauve vertical pair and single cancelled by "AMOY/A" c.d.s. and showing circular-framed "R" with, on reverse, Hong Kong (30.3), San Francisco (20.4) and arrival (7.5) d.s.; some light bends and minor soiling. Scarce and attractive. Photo