Classical Greek sources — Aeschylus, Xenophon in his Anabasis, and Apollonius of Rhodes — attribute to the Chalybes, a people who inhabited the mountainous Pontus region of northern Anatolia, the development of quenching and carburization techniques for iron to produce a hardened metal equivalent to steel; indeed, the Greek term for "steel" itself (χάλυψ, chalybs, origin of the Latin chalybs) derives from this people's name. It is important, however, to distinguish between this Greek-origin historiographic attribution — which dates the innovation to around the 10th century BC rather imprecisely — and the direct archaeological evidence: spectrometric analyses of iron artifacts from the Pontus region show significant manganese levels (between 1.45% and 4.65%) that enabled steels hardened through intentional carburization, but this evidence dates rather to the 7th century BC, several centuries after the traditionally cited date. The ethnic identity of the Chalybes is also debated: while the Greeks considered them Scythians, some modern historians link them to Georgian or Kartvelian peoples of the region. The case of the Chalybes thus offers a clear example of how a technical attribution documented by a particular historiographic tradition (the Greek one) may not exactly coincide with what direct archaeological evidence can independently verify.