Ostrich eggs up to 7,500 years old found next to ancient fire pit in Israel

A well-known riddle compares an egg to treasure, asking: A box without hinges, key or a lid, yet inside golden treasure is hid. What am I?

source https://www.cnn.com/2023/01/13/middleeast/ostrich-eggs-discovery-israel-scn-scli-intl/index.html