This Tweet by NASA Space Flight Editor Ian Atkinson says:
Some pictures from the Cathedral before the event starts, they have a table set up with artifacts from Apollo 8, including the flown flight plan!
There's also a window dedicated to Space exploration, with a moon rock in the glass (inside the white circle near the top).
Is this just space lore, or is there really "a moon rock" in the glass? If there is, how did it travel from the Moon to the window, and if known, from where on the moon is it from?