"Amelia, " said Steven seriously, "I recently sent a team of unspeakables to Gringotts. Their job was to investigate all of the vaults at Gringotts and search for any items or objects that produced that distinctive Horcrux heartbeat sound. The unspeakables have the authority to search and investigate the vaults at Gringotts but NEVER have the authority to remove anything. All they can do is report anything suspicious. As the goblins would not understand the nature of Horcruxes, I instructed the unspeakables not to tell the goblins about any Horcrux issues. The unspeakables told the goblins that nothing was amiss after their investigations, which aren't totally unusual, but an unspeakable named Otto Observe informed me that he could hear that distinct Horcrux heartbeat on a small golden cup in Bellatrix Lestrange's vault."

"What do we do now then?" Amelia asked Steven.

"No witch or wizard, other than Bellatrix herself, will be able to remove the cup. And if you try to use Polyjuice Potion, well that won't work. All high security vaults are bewitched with the Thief's Downfall, a curse that washes away all enchantments, including and especially imposter disguises, the nanosecond a person other than the owner of the vault enters it, " explained Steven calmly.

"What do you suggest we do?" Amelia asked Steven.

Amelia felt certain from Steven's calmness that he had a plan.

"House elves can Apparate into and out of the vaults without detection, Gringotts and its spells do not recognize house elf magic. A ministry house elf could be assigned to Apparate into Bellatrix Lestrange's vault, remove the golden cup, and bring it back to the Ministry of Magic. I would then take it back to the Dark Magic Room where I would conjure Fiendfyre to destroy it, just like with the diary, " explained Steven.

"House elves are experts at very precise Apparition and Disapparation, " mused Amelia, "I think what we should do is tell the house elf we assign to this task to Disapparate from Bellatrix's vault directly into the Dark Magic room. In that way the cup won't be seen around the Ministry and arouse curiosity. But as soon as the house elf has the cup in the Dark Magic room, we let him go so that we don't put him at any risk from the Fiendfyre."

"Very well. " said Steven, "I will go up to Ministry House Elf Room and inform the house elf Troggle that his services are needed."

"He's the best one for this job, " agreed Amelia, "Have at it. I'll wait in the Dark Magic Room."

"Okay, " said Steven simply.

Steven retrieved his wand from his right hand pocket and a piece of parchment form his left hand pocket and proceeded to the Ministry House Elf Room.

"Troggle, " called out Steven and a big house elf with large hands came forward.

Next nanosecond, Steven pointed his wand at the parchment and a set of instructions appeared on it that he quickly handed to Troggle.

Steven then went to meet Amelia in the Dark Magic Room.

Troggle quickly read the instructions and the parchment then collapsed and disintegrated.

Troggle Appaarated into Bellatrix's vault.

As house elves have very sharp vision, with particularly good periphery vision, Troggle quickly found the golden cup he had been instructed to bring back to the Dark Magic Room.

Troggle quietly picked up the cup and Disapparated from Bellatrix's vault and reappeared in the Dark Magic Room.

"Well done, Troggle, " said Steven and Amelia together.

"Troggle, you've done your job and done it well, " said Steven proudly, "You need to return to the Ministry House Elf Room now."

And Troggle returned to his room

Steven now held the cup up to his right ear.

"This is definitely a Horcrux, " said Steven firmly, "The heartbeat is unmistakable.".

Amelia, with a sinking feeling in her heart, saw a badger engraving on the cup.

"A badger?" piped up Amelia sadly, "Then this cup would have belonged to Helga Hufflepuff."

"You know, Amelia, " said Steven wisely, "If Voldemort would take artifacts from Ravenclaw and Hufflepuff and turn them into Horcruxes, I've got to think he turned an artifact of Slytherin into a Horcrux as well."

"You're probably right about that, Steven, " said Amelia matter of factly.

"But we've got a task at hand, " said Steven in a serious voice as he refocused.

"You know what to do, Steven, " said Amelia respectfully, "I'll stay here to supervise you."

And so, Steven raised his wand and performed a nonverbal spell to create the needed Fiendfyre, immediately stepping back from it and throwing the Golden Cup Horcrux into it.

Steven quickly doused the flame to see that the Golden Cup Horcrux had been charred. Steven picked it up and it crumbled into ash, which Steven vanished.

"Well, " said Steven in a satisfied voice, "If our theory about the Horcruxes is correct, they are half gone now."

"We've definitely made progress, " said Amelia in a businesslike voice, "If we can get rid of all the Horcruxes before Voldemort can rise again, we'll have an advantage over him he won't know about."

"That's why identifying what the Horcruxes are and finding and destroying them is the number one priority at the Department of Mysteries right now, " said Steven seriously, "We know what could be at stake here."