We examine the significance of a kilo pohaku, or "stone mirror" -- a small volcanic stone disk used for viewing reflections -- discovered deep inside the ancient Makauwahi Cave on the island of Kaua'i. This extremely rare specimen encapsulates the great mystery of Hawaiian archaeology, which relies on reconstruction from rare stone, bone, and shell objects, and also the threats facing the historical sites and artifacts of ancient Hawaii in a time of natural disaster and rapid development. Special thanks to: Maui Historical Society, the National Tropical Botanical Garden, Makauwahi Cave Preserve, Kaua'i Community College, Kaua'i Historical Society (particularly Mona), Dr. David Burney, and Jason Ford. Suggested further reading: David Burney, "Back to the Future in the Caves of Kaua'i." Image: Kilo pohaku, cowry beads, & bone bead found at Makauwahi Cave; image courtesy of David Burney. An image illustrating the immersion method of using a kilo pohaku can be seen on the website of Papahana Kuaola here: https://papahanakuaola.org/kukulu-kahua-2/kukulu-kahua-types-and-uses-of-pohaku/ Suggested historical preservation organizations for donations: --Makauwahi Cave Reserve: http://www.cavereserve.org/donate.php --Maui Historical Society: https://mauimuseum.org/donate --Lahaina Restoration Foundation: https://lahainarestoration.org/donate/ --Kaua'i Historical Society: https://kauaihistoricalsociety.org/donate/ Please sign on as a patron to hear the next lecture on the origins of the First World War: https://www.patreon.com/user?u=5530632