Random Things in a Forgotten Magic Museum

From top left, then clockwise:

1. Mask - Sits alone on a floor while passing through a room. It's made of stone.  If worn on the face for 7 minutes, it takes on the facial features of whoever last wore  it for 7 hours, then it reverts back to stone. A useful disguise. (The last wearer stored could give you a clue about the previous inhabitants of the museum)

2. Mimic Jar - A NPC intelligent mimic that wandered in here ages ago and got lost.  Is super helpful and happy to see strangers. Offers to hold things, explore rooms, etc. Just don't let it get too hungry...

3. Canopic Jars - ensorcelled jars that hold the remains of former librarians. The heads can speak, and were designed to hold all the memories of their owners, but the magic has decayed over time...

4. Serpent Sigil. Ancient statue to a potent cult figure.  Showing it any sort of deference results it animating and trying to bite you. If you let it bite you,  you lose 1d4 hp permanently but you're affected as if by a periapt of proof against poison.

5. Armillary Sphere. This room sized sphere radiates palpable magic. Anyone who studies it for more than a few seconds must save or be hypnotized. The viewer must then obsessively study the sphere from all angles for at least 36 hours, after which they fall into a coma for 12 hours and can't be woken up. When they wake up, the affected now has perfect direction sense over land or sea for the next 36 months. After that, they won't be able to find the bathroom on their own for 12 months. They also learn a secret (as per the hermit background) The Sphere has no effect on elves.

6. Rock Collection. A vaguely magical collection of polished rocks. Removing a single rock seems to lessen the enchantment somehow.  These rocks were once a complete collection of depleted Ioun Stones  - the original enchantments have worn away over time. Probably valuable to a church of Ioun or a Collector.

7. Song Book. Contains various hymns, prayers, as well as popular ditties from another age.  Gives a bonus to performance checks.

8. Skull reliquary - the skull of the founding librarian was preserved in this reliquary.  Unlike the canopic Jars it has infallible memory. However the spirit in the reliquary doesn't trust the party at all and will treat them as grave robbers, giving them useless information or sending them into traps. If the reliquary is damaged or opened it summons the ghost of the librarian who is itching for a fight.