Advances in obsidian hydration dating by secondary ion mass spectrometry: World examples

Since 1960 the potential of obsidian as a chronometer in archaeology has been subjected to several drawbacks and studies. While economical, simple and fast, obsidian hydration dating today is generally unreliable. A novel approach towards obsidian hydration dating, named SIMS-SS, has recently been initiated based on modelling the hydrogen profile acquired by secondary ion mass spectrometry (SIMS), following Fick’s diffusion law, and the rationale of surface saturation (SS) with water molecules. The new nuclear method is presented with significant refinement regarding numerical calculation of age parameters, the suitability criteria of the sampling area and the spectral shape of the concentration dependant H+ profile. A reappraisal is applied to thirteen obsidian specimens from all over the world ranging some 100’s to 30,000 years old. The results reinforce the precision and reliability of the SIMS-SS method, enhancing its wide applicability.