1990年中国人民银行第四版人民币1元单面背面黑白试印样票,古币水印,PCGS Banknote 61PPQ。 非常罕有。People s Bank of China, 1 yuan, 1990, uniface reverse printer s proof, black on white, the Great Wall at centre, watermark of spade money,(Pick 884e-f), PCGS 61PPQ, uncirculated, very rare.