Determining Die Marriage Rarity

Survival estimates for each date and mintmark were combined with die marriage distribution data to determine the rarity of each die marriage. The die marriage distribution data were obtained by analyzing the Heritage Archive records of coins sold through Heritage Auctions. Heritage was chosen for several reasons:
  1. The quality of the pictures available in their on-line archives usually allows attribution. This is true for most Seated Dollars (and other series as well) sold after 2005, and for some prior to that date.
  2. Their archives include enough coins for each date to create a statistically valid database.

The table below is an example of this die marriage rarity determination for coins dated 1870-CC.

1870-CC Die Marriage Rarity*

Die Pair Variety # of Examples % Projected Examples (750 Total) Rarity
1-AOC-17323.10%173R4-
1-B00%0Unknown
1-C00%0Unknown
1-D00%0Unknown
1-E00%0Unknown
1-F00%0Unknown
2-AOC-2257.91%59R5
2-BOC-3165.06%38R5+
2-C00%0Unknown
2-DOC-7319.81%74R5-
2-EOC-85517.41%131R4
2-F00%0Unknown
3-A00%0Unknown
3-BOC-5175.38%40R5+
3-COC-430.95%7R7
3-DOC-6185.70%43R5+
3-E00%0Unknown
3-F00%0Unknown
4-A00%0Unknown
4-B00%0Unknown
4-C00%0Unknown
4-D00%0Unknown
4-E00%0Unknown
4-FOC-97824.68%185R4-

*This table is based on data through January 9, 2020


The raw data set on which the preceding table is based contained 374 individual auction records, representing Heritage records for auctions from 1999 through January 15, 2020. For 1870-CC, many of the recorded sales prior to 2006 could be used, since 1870-CC die marriages can often be attributed from lower resolution photos. Wherever possible attempts were made to eliminate sales records which represented repeated sales of the same coin. Despite these efforts, weíre sure that we didnít get them all, and some duplication still exists. We donít believe that this duplication has a significant effect on the final rarity estimates. As Heritage adds additional sales to the archives weíll update our records, and as required reflect the updated data on this website, and in subsequent revisions of our book.

The raw data on which the rarity estimates are based are contained in spreadsheets, one representing each Seated dollar issue. Each line item documents the information related to an individual sales record. The effort to create these spreadsheets was major. The entire effort took over 2 years. These spreadsheets are available from the authors on request. To conserve space, they arenít included either on this website or within our book.



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