The widthMm field captures an object's width in millimeters, measured perpendicular to its lengthMm. Together the two dimensions, plus thicknessMm, describe the size and proportions of a find — important for classifying tools, sherds, and other shaped objects. The field is optional, so you can omit it for bulk lots or pieces you have not measured. Stored as a decimal, it keeps the fractional precision needed for fine metric recording and downstream comparison across an assemblage.
Technical section
Data model, API, and internals — visible to developers.