The Smithsonian trinomial is the universal naming convention for archaeological sites in the United States — a code combining the state number, a county abbreviation, and a sequential site number, such as 41BX180. Recording it in smithsonianTrinomial ties your Site to the official state and national site inventory, which is essential for reporting and for cross-referencing against records held by review agencies. It is optional because a newly discovered site may not yet have been assigned a trinomial. Within your tenant the value must be unique, so the same site is never accidentally entered twice under different names. It complements the informal siteName used for everyday reference.
Technical section
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