The work of archaeologists is used to investigate how color classification, an enduring topic within philosophy and cognitive science, is organized as historically structured, accumulative co-operative practice. To systematically describe the color of the dirt they are uncovering, archaeologists use a Munsell color chart, the product of a history of research by color scientists. Archaeologists adapt the chart to the specific needs of their work by cutting holes beside each color patch. A trowel containing the dirt to be classified is moved from hole to hole to find the best color match. The Munsell chart provides three different signs for describing the same color: a color patch containing an example of the color, its grid coordinates within an analytic color space, and a vernacular name. Each form of semiosis makes possible different action. Color classification is made relevant by the task of filling out a coding form, a textual inscription that ties the outcome of this task into an ensemble of encompassing activities. Inherited knowledge instantiated in a material artifact is laminated into the contextures of mutually elaborating linguistic and embodied semiotic fields that make possible the distinctive work that constitutes archaeology.

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