Turning Objects into Data
A thousand potsherds are noise until you classify them. Typology sorts artifacts into types by shared attributes — form, material, decoration, technique — and a good type is one that clusters in time or space, so that its presence carries information. Types are tools, not truths: the "type" of a pot is a hypothesis that these fragments were made to one shared idea.
Archaeologists distinguish:
| Term | Meaning |
|---|---|
| Attribute | A single observable feature (rim shape, temper, glaze color) |
| Type | A recurring bundle of attributes |
| Assemblage | All the material from one context — the type mix at one moment |
| Industry / tradition | Types sharing a technological lineage over time |
Seriation: Chronology Without a Lab
Before radiocarbon, how did anyone order sites in time with no stratigraphy linking them? Seriation, the elegant answer, rests on one fact of fashion: a style is rare when new, becomes common, peaks, then fades — its popularity over time traces a lens shape. Plot each type's frequency as a horizontal bar per time-slice and stack the slices in the order that makes every type swell and shrink smoothly, and you get the famous "battleship curves." The single arrangement that makes all the curves rise-and-fall cleanly is the chronological order.
Flinders Petrie invented the method (sequence dating, 1890s) to order thousands of Egyptian graves that no stratigraphy connected — sorting them purely by the changing frequencies of their pottery types.
Direction is the catch: seriation delivers the sequence but not its polarity — the battleship curves look identical run forwards or backwards. An external anchor (one C-14 date, one stratified find, one historical link) tells you which end is early. Relative method, absolute anchor: the recurring partnership of the whole chapter.