Khao Sek, a coastal settlement located in the Upper-Thai Peninsula and 80 km south of the early urbanized port of Khao Sam Kaeo in the Chumphon province, yielded an impressive quantity of glass waste and ornaments suggesting that glass bracelets and beads were manufactured at the site as early as the 4th c. BCE. This article discusses the glass material found at Khao Sek using typological observation but also elemental analysis with laser ablation – inductively coupled plasma – mass spectrometry. Beyond obvious morphological resemblance, compositional analyses of the glass confirm similarities between the glass industries at Khao Sam Kaeo and Khao Sek and the existence of a fairly standardized glass ornament production at an early period. This article provides new arguments to discuss the fashioning of a regional standardized craft system as early as the mid-first millennium BC and its role in …