Global perspectives on obsidian studies in archaeology

For more than a half-century, obsidian provenancing has underpinned many archaeological investigations of peoples of the past. The pace of obsidian studies in this regard has gathered significantly since around 2007, and we review the literature to gain a sense of where this momentum has come from, and what it heralds. In part, there is a data revolution underway, arising thanks to the capabilities for rapid survey and analysis enabled by field-portable analytical equipment. Obsidian studies are also gaining a stronger foothold in regions of the world where the approach was previously under-exploited. Our survey spans progress made in obsidian studies in the Mediterranean, Central Europe, the Near East, the Caucasus, Northeast Asia and Tibet, the Eurasian Arctic and Alaska, Southeast Asia, the Americas, Oceania, and Africa and Arabia. We also consider methodological issues related to compatibility of differing geochemical analytical techniques, and the state of the art in obsidian geochemical classification. The proliferation of new observations brings opportunities in terms of development of regional and global databases, as well as challenges of calibration and validation of analyses made by different scientists and laboratories employing diverse instrumentation. Obsidian provenancing demonstrates the astonishing ranges of our ancestors' interactions and networks, sometimes exceeding 1000 km and involving maritime transport.