The rings used by Digory and Polly in The Magician’s Nephew, which drew them to The Wood Between the Worlds.
The rings also generate a personal environmental field that lets the user breathe and survive in the vacuum of space, etc. I want one.
The Tutmose amulet found by high school science teacher Andrea Thomas, which gave her “the powers of the animals and the elements” in The Secrets of Isis. On behalf of a generation of men who were too old to be watching Saturday morning kids’ shows. I would also like it to be given to me by Andrea Thomas herself.
If I listened to that, I’d never post here
Putting on the Enchanted Crown of the Sepsis Whore was a really bad idea, though.
Which of the many nipple-rings acquired by Princess Donut and Carl would be the best?
Saturday morning cartoon: Shazam! (?) My memory is failing, but didn’t the two kids have a half ring each and putting them together summoned the titular genie?
There is no way this will count, but I’ll mention it in passing and maybe someone will have a larf: when Moon Zappa sings (talks through) “Valley Girl,” she mentions her history teacher who is “Mr. Bufu” — that’s Lord, God, King Bufu and he plays with all his rings. I am sure!
Close: Shazzan. But you got the mechanic right.
The golden headband of Ozymandias!
(In the prequel comic, he uses it as a throwing weapon!)
In the Dresden Files books, the wizard Harry Dresden carries a variety of jewelry as tools of his trade: a pentagram amulet he uses as a symbol and occasional flashlight, a shield bracelet (a charm bracelet with shields) that can be used to create force fields to protect him from attacks, and rings that store kinetic energy every time he moves his arms, which can be released all at once in case of emergencies.
The Queen’s diamond necklace which D’Artagnan and chums have to recover in The Three Musketeers
The six Signs (a form of brooch/belt decoration) which Will Stanton has to collect in The Dark Is Rising.
The Blue Carbuncle, the theft of which is solved by Holmes in the eponymous Adventure.
Sadly, Joanna Cameron died in 2021.
On a completely unrelated note, there were the Power Pasties, worn by Amora, high priestess of the goddess Yoni, in the movie Flesh Gordon.
It only now occurs to me that the OP was specifically wanting jewelry that had some type of power and not just plays a visible role in the story. So any of my replies that were off-topic were unintentional.
Oof, me too. Dark Is Rising still counts, the other two don’t.
Also the Arkenstone, but I believe the OP was looking for Jewelry and not just gems.
As with much (most?) of Tolkien’s jewelry that’s the kind of thing it’s safer not to have… I don’t think any of Feanor’s sons is still around but… why take the risk?
I don’t think I’ve ever seen any movie or TV portrayal of Aladdin that portrayed the ring. It is used a lot in the original story.
Dr. Strange’s Sling Ring, which he uses to create teleportation portals.
All but one is accounted for and the last hasn’t been seen since the end of the 1st age and is presumed dead. Maglor the Minstrel who actually helped raise Elrond & Elros is almost surely dead, but no verification that he is.
Maglor was the second eldest of the 7 sons.
Yes, Maglor, I remembered that a bard was not confirmed dead but I didn’t remember the name.
So, as I said, better not risk it, the shadow of the Oath is long and ominous…
The Ring of the Nibelung, which was probably an inspiration to Tolkien.