When did Dumbledore destroy the Horcrux ring?

Question

In book 6, Harry Potter and the Half-Blood Prince, in Chapter 4, when Dumbledore takes Harry to meet Slughorn, he is using Gaunt's ring to attract Slughorn:

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.

Than later on in Chapter 10, after seeing Odgan's memory, the ring is still in Dumbledore's office:

He turned away again, and was almost at the door when he saw it. Sitting on one of the little spindle-legged tables that supported so many frail-looking silver instruments, was an ugly gold ring set with a large, cracked, black stone.

Then, at the end of Chapter 13, after Dumbledore's memory with young Tom Riddle, comes this:

Harry got to his feet. As he walked across the room, his eyes fell I upon the little table on which Marvolo Gaunt's ring had rested last time, but the ring was no longer there. "Yes, Harry?" said Dumbledore, for Harry had come to a halt. "The ring's gone," said Harry, looking around. "But I thought you might have the mouth organ or something."

So we see that the ring was destroyed somewhere in-between - that is, in the middle of Harry's 6th year.

But in the 7th book, Harry Potter and the Deathly Hallows, in Chapter 33 "The Prince's Tale", we learn that:

And now Harry stood in the headmaster’s office yet again. It was nighttime, and Dumbledore sagged sideways in the thronelike chair behind the desk, apparently semiconscious. His right hand dangled over the side, blackened and burned. Snape was muttering incantations, pointing his wand at the wrist of the hand, while with his left hand he tipped a goblet full of thick golden potion down Dumbledore’s throat. After a moment or two, Dumbledore’s eyelids fluttered and opened.
“Why,” said Snape, without preamble, “why did you put on that ring? It carries a curse, surely you realized that. Why even touch it?”
Marvolo Gaunt’s ring lay on the desk before Dumbledore. It was cracked; the sword of Gryffindor lay beside it.

So the ring is destroyed in the same night Dumbledore found it!

Can someone solve the conflict?!

Answer 1

The answer is that there are two types of "destroying" going on here.

On the night that Dumbledore finds the ring, he uses the sword to destroy the fragment of Voldemort's soul. The ring and the Resurrection Stone are "cracked," because he used the sword on it, but it's still in one piece. Dumbledore continues to wear the ring for unknown reasons, probably to protect the immensely powerful Hallow it's connected to.

Halfway through Harry's sixth year, Dumbledore destroys the actual ring. The Resurrection Stone is removed and placed inside an old Snitch, and Dumbledore changes his will to pass it on to Harry.

Answer 2

Dumbledore was excited to find the Hallow, and in his haste to see his sister, he puts on the ring invoking the curse meant to protect the horcrux.

When Harry goes inside Snape's memory in the final book, he sees that the ring has been cracked on the day Dumbledore found it (the stone is cracked). The cracking open of the stone doesn't destroy its ability to make its holder see and interact with the shadows of the dead. Which is why Dumbledore continues to wear the ring and may also explain the great deal of knowledge that Dumbledore had, that he could have gleaned from the dead.

However, cracking open of the stone by the sword of Gryffindor only destroyed the horcrux that Voldemort made. In Harry's sixth year, he is only taught about the horcruxes and not about the Deathly Hallows, therefore he doesn't need to know what the significance of the stone is. When the ring disappears from Dumbledore's office, it doesn't mean that the ring/horcrux was destroyed, Dumbledore merely inserted the stone in the snitch that is bequeathed to Harry, knowing Harry will figure out to use it when needed.

Answer 3

When Dumbledore finds the ring it has 2 "powers" -- the original 1/3 hallow ghost summoning power plus the 1/7th Voldemort soul-bearing Horcrux power. Dumbledore was too enthusiastic about the Hallows feature (to reunite with his dead sister) and put on the ring ... Invoking the Horcrux curse first... Thus causing damage to himself, requiring Dumbledore and Snape to blast the object and destroying the Horcrux aspect, causing a crack to form on the ring. The Hallow aspect is intact after the damage, as Dumbledore continues to posess the ring, and Harry Later uses it to summon his "ghosts" before the final battle.

Answer 4

The reason Dumbledore kept the ring on even though it was cursing him and slowly killing him was because the stone was contained in the ring was actually the resurrection stone (one of the Deathly Hallows).

That's why Voldemort's uncle, Morfin Guant prized it so much as a family heirloom. Dumbledore kept it on because at that point in time it allowed him to see his dead sister, Ariana Dumbledore (who's death he feels guilty for). As long as he wore the cracked ring that cursed him he was able to be with Ariana again (even though nobody else realized it at the time except for him - and probably Snape).

Answer 5

Dumbledore destroyed the ring after his duel with Voldemort in the Ministry Atrium, but before Harry Potter began his sixth year, that is, prior to the events of Half-Blood Prince book.

Here is the quote:

HPATHBP, Chapter 4:

"Yes,” said Dumbledore quietly. “A terrible loss. She was a great witch. Just up here, I think — ouch.” He had pointed with his injured hand.

“Professor, what happened to your — ?”

“I have no time to explain now,” said Dumbledore. “It is a thrilling tale, I wish to do it justice.”

This conversation between Harry and Dumbledore is part of Dumbledore's first appearance in Half-Blood Prince. In Dumbledore's last appearance in Order of the Phoenix, he doesn't have it yet.