A U. S. pattern coin concordance is a consensus regarding observations of details and opinions from cataloguers of U. S. pattern coins. Cataloguers have relied, in some respects, upon the opinions set down by earlier cataloging efforts. Frequently there are consistencies of opinions and occasionally there are differences of opinions. Sometimes there are erroneous opinions. A concordance which co-mingles the major catalogers of modern times: Edgar Adams and William Woodin, J. Hewitt Judd, Don Taxay and Andrew W. Pollock III offers a wide range of opinions. Some opinions lack justification and require explanation. Our pattern concordance makes every effort, where possible, to provide new and compelling information. Scanning Electron Microscope with Energy Dispersive x-Ray (SEM-EDX) analysis technology is available today. Coins can be tested non-destructively for elemental analysis. If one is interested in verifying the attribution of a coin, it is possible to do so. Encapsulated coins may be sent to the service that encapsulated the coins and for a fee, a SEM-EDX analysis will be performed. Your coin will be returned to you with the scientific analysis from the independent testing lab and the coin will be in a new holder, possibly with a different attribution and possibly an attribution for a more valuable or a less valuable coin. Seventeen of fifty coins submitted for analysis by this author were returned with different attributions than the original encapsulation certificate. Some coins proved to be more valuable and some proved to be less valuable. The grading services made appropriate adjustments when their error of attribution was determined to have been responsible for the coin’s increased acquisition cost. One of the side benefits of testing your coins scientifically is that we can include your analysis in our concordance for all, if we are provided your analysis. Never before has it been possible to have a register of U. S. pattern coins that can be updated as frequently as needed with the latest discoveries, co-mingled with the previously published catalogues, and available to anyone at no charge who has access to the Internet. Unlike a book on U. S. patterns which gets published and maybe years later is republished with new information, one will not have to wait ‘years’ to read the most up-to-date, state of the art entries. Our pattern concordance is unnumbered. We only will modify an existing number by decimalizing and then suffixing it. Not having to contend with catalog numbers comes as a blessing in that we can fit new discoveries between existing categories. Our concordance generally follows the order used by Pollock in his numbering system. Part of the reason for this is that Pollock had more issues defined than did Judd. We have modified the Judd numbers, in the case of the Postage Currency ten cent coins of 1863, by placing after the Judd number a decimal point and then a number: 1, 2, 3, etc. The grading services primarily use the Judd numbering identification system for the certification of coins contained in their plastic holders. This generation of pattern coin collector's familiarity and acceptance of the Judd’s identification and numbering system, seems inexorable. It is not necessary to replace the closed end numbering systems of Judd or Pollock with our decimal numbering system. We wish only to supplement and clarify, rather than replace, their numbering systems. The Pattern Concordance columns reading from left to right are: Year, Denomination, Metal, Edge, Photo link, Pollock number, Judd number (modified,) Adams and Woodin number, Taxay number, Rarity, Class, and Additional Information. For example, check out J-325.3: 1863, Ten cents, Silver, Plain edge, Photo available, Pollock number 390, Judd number 325.3, Adams and Woodin number 388, Taxay number 341, Rarity 8, Fantasy piece class, Metallurgical trial piece, 38.3 grains, possibly struck on a dime planchet, Silver 96% Copper 4%. Our system is infinitely expandable in that one can add new varieties simply by increasing the tenth’s position or can modify the tenth’s position for sub-varieties equally easily. Collectors, dealers, authenticators, researchers, museums, grading services, and any other interested party should make available to our pattern club the analyzed result of their coins for inclusion in our database. Although the author’s specialty is U. S. Postage Currency pattern coins of 1863 and the related dates of 1868 and 1869, which have demonstrated the need for testing, several other issues are equally in need of testing. If you own any of the following pattern coins and have them tested, please make the findings available to our Pattern Club. Any patterns struck in the following metals: billon, oroide, white metal, steel, silver-nickel, German silver, pure nickel, or with listed percentages of metals, any 1854 Liberty Seated cents, any 1864 cents J-353 through J-362, any 1896 coins, and of course any 1863, 1868, and 1869 Postage Currency and related dimes. The decimal numbering system should not be suffixed for coins that are untested or unverified without stating ‘untested’. All coins need to be SEM-EDX tested or similarly scientifically analyzed for inclusion in this system. David Cassel is writing a book entitled United States Postage Currency Pattern Coins which is expected to be available later this year.