The most valuable find...
A pre-shattering time capsule is found on Earth. In 2019, the time capsule was put into a cavern that was deliberately collapsed back in that prehistory era only to be opened, slowly, by centuries of erosion and earth shifts. Several teachers and historials carefully gathered text books, history books from around the world, old newspapers, maps copied old scrolls, various sets of encyclopedias, bibles from as many cultures as possible, books on languages from around the world, to name but a few of what was in there. It was an incredible treasure trove of history. From the ancient histories, to the civil war, to the history of the various earth world wars, to things like the great depression to the modern era. The history books were from many nations and various cultures. And not just history books, but recipe books, people's personal diaries and photos as well. The capsule being a hard, resilient plastic container filled with inert nitrogen to try to prevent oxidization of these assets.
And who found this treasure trove to start? A homeless, hungry, twelve year old who was exploring caverns and a havenworlder who had come to visit earth and gotten lost from the tour group.