1948年中央银行50元试色样本，编号56ZO 00000，前后均为正面票样，左右倒转，以绿色印刷（与流通票所用黑色有别），中间有折，左下有小黑点，AU品相，富有趣味的一枚。Central Bank of China, 50 yuan, progressive proof, likely series of 1948, serial number 56ZO 00000, green on multicolour, Chiang Kai Shek at centre, an extremely interesting note for three reasons: the obverse design is printed on both sides, the printing is the mirror image of what it should be (i.e. like a brockage) and the colours are very different to the issued note (which is black)(Pick 404 for type), central fold, small black ink mark lower left corner, almsot uncirculated and extremely fascinating
