Question 2: Yellowstone National Park has a mountainside containing obsidian located between ________ and the Norris Geyser Basin, and deposits can be found in many other western U.S.
Question 4: ________ were once thought by many to be obsidian produced by lunar volcanic eruptions, though few scientists now adhere to this hypothesis.
Question 5: In ________ obsidian tools from Chaitén Volcano have been found as far away as in Chan-Chan 400 km north of the volcano and also in sites 400 km south of it.
Question 7: Similar tracing techniques have allowed obsidian to be identified in Greece also as coming from Melos, Nisyros or Yiali, islands in the ________.