When Dumbledore and Harry visit Horace in HBP, Horace seems to react to the ring that Dumbledore was wearing. Does he recognise this from Tom Riddle wearing it when he asked about Horcruxes or why did he react like that?

"I am undoubtedly slower than I was. But on the other hand..." He shrugged and spread his hands wide, as though to say that age had its compensations, and Harry noticed a ring on his uninjured hand that he had never seen Dumbledore wear before: It was large, rather clumsily made of what looked like gold, and was set with a heavy black stone that had cracked down the middle. Slughorn's eyes lingered for a moment on the ring too, and Harry saw a tiny frown momentarily crease his wide forehead." Half Blood Prince - chpt 4

  • Perhaps he recognized 'Grindelwalds' Mark on it.
    – SBoss
    Dec 12, 2014 at 16:35
  • As you yourself said, the ring was known to him from Tom Riddle. I'm unsure why you don't think that your own question doesn't serve as its own valid answer. Dec 13, 2014 at 3:33
  • @ DVK - fair enough thats possible :-)
    – BP_Phoenix
    Dec 13, 2014 at 16:31
  • 1
    @BP_Phoenix - edit the answer out of the question and into self-answer, perhaps? :) Dec 15, 2014 at 17:55
  • Perhaps he thinks it's odd to wear a ring that is clumsy and obviously damaged - "that had a crack down the middle". Dec 21, 2014 at 14:09

2 Answers 2


I think he remembers the ring from his memory.

More specifically, I think he's looked at the memory recently (in the Pensieve sense of full scene detail, not just a fuzzy recollection).

When Harry and Dumbledore visit Slughorn, it sounds like Dumbledore has already reached out to Slughorn:

“This,” said Dumbledore, moving forwards to make the introduction, “is Harry Potter. Harry, this is an old friend and colleague of mine, Horace Slughorn.”

Slughorn turned on Dumbledore, his expression shrewd.

So that’s how you thought you’d persuade me, is it? Well, the answer’s no, Albus.”

Half-Blood Prince, chapter 4 (Horace Slughorn)

Slughorn's not stupid; he knows why Dumbledore wants him out of retirement. Dumbledore wants his memory of Riddle at school.

It's likely that he revisited the memory before Harry and Dumbledore arrived, looking for incriminating details (and modifying appropriately). But the forged memory still includes the image of Marvolo's ring:

His right hand lay negligently upon the arm of his chair; with a jolt, Harry saw that he was wearing Marvolo’s gold and black ring; he had already killed his father.

Half-Blood Prince, chapter 17 (A Sluggish Memory)

If he remembers this detail, then seeing the same ring on Dumbledore's hand would confirm his suspicions. Dumbledore is looking for information about Riddle as a student, and Slughorn knows what he said. He feels guilty, but he’s trying not to show it.


Slughorn must have known that Riddle had a gold and black ring on around that time.But I don't think he knew that the ring was a heirloom of Salazar Slytherin or that it belonged to Marvolo Gaunt.If he did, he would have got suspicious and deleted that part of the memory too.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.