Go Forward

Geochemical standardization of obsidian

The Chemical Laboratory is promoting the international project for "geochemical standardization of obsidian".

Geological standardization is moving forward thanks to tight international collaboration.
The Chemical Laboratory is especially promoting the international project for “geochemical standardization of obsidian”. This project was advocated by Prof. Akira Ono during the International Obsidian Workshop in Nagano, and began on November 6, 2011. The aims of this project are 1) comparing chemical data among laboratories, and 2) the establishment of standard geochemical reference samples for the nondestructive analysis of obsidian artifacts. Obsidian used for the standardization was obtained from the following locations: Shirataki Hachigosawa (JOSH-1), Shirataki Ajisai-notaki (JOSA-1), Oketo (JOO-1) and Rubeshibe (JOR-1), which are all in Hokkaido, Japan, and are shared at the COLS head office in Nagano (see photo). Analytical methods include ICP-MS, INAA and XRF, and analyses will be performed at six laboratories.
Although geochemical reference samples comprised of solidified natural obsidian are necessary for the nondestructive analysis of obsidian, the establishment of such has yet to be accomplished. Thus, this project is the first attempt in the world at doing so, and offers a good chance to establish a worldwide protocol for the nondestructive analysis of archeological obsidian artifacts, as well as a method for the estimation of the source of archeological obsidian artifacts.