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Does anyone have credible information, with reference, detailing how many obverse and reverse 1870 dies were utilized or consumed? Perhaps someone knows of a researcher who has conducted a rudimentary study with images? I've identified 5 unique reverse dies based on die breaks, and position of '0' in the date, from a very small sample size of 18 pieces. I suspect at least 10-12 reverse dies were utilized. The first instance of The Royal Mint publishing die use data was 1884, so the 1888 50c is the first official documented correspondence of die use for that denomination.
Thanks, RD