Afterwards, Rarity decided that the less she allowed herself to dwell on the rest of the night's activities, the better. Never in all her life had she imagined that she would willingly traipse through the Ponyville waste water drainage system—she would not, would not, would not allow the word 'sewer' to so much as quiver across her thoughts. But through seemingly endless miles of stone tunnels she'd trudged as the night wore on, the glow of her horn the only illumination and a growing annoyance her only emotion.
Fortunately, she didn't have to worry about behaving so uncouthly as to give voice to those frustrations. Not while she had Rainbow Dash stomping along the street beside her. "Six hours!" Rainbow waved a wing toward the eastern horizon, now substantially brighter than just a few moments before. "And the only action was that prowler we chased around Twilight's castle!"
Not knowing why she bothered, Rarity said, "That was Owlowiscious."
"You don't know that!"
As amusing as this argument had been the first five times they'd had it, Rarity declined to participate in a sixth go-round. "What I do know," she said instead, "is that we are returning emptyhoofed."
And, oh, how it rankled. It made Rarity squint and puff and imagine some dunderhead scooping up her diamond and throwing it into a display case, sucking the life and the breath out of the stone. For all that she found it difficult at the moment to think good thoughts about Fashionably Late, at least the mare had understood that pieces like the Azdariz needed to be out, needed to be admired, need to know the kiss of sunlight and the gentle cradle of a mare's throat rather than be locked away in some museum or private collection somewhere.
But after having rooted through every drain grating and catch basin in Ponyville as well as every spot that Fashionably Late could conceivably have visited... Rarity reached up to rub her eyes only to meet the cloth of the Mare-Do-Well mask she was still wearing. Forcing her teeth not to grind, she pushed the words out through her reluctant throat: "Somepony must've already found it."
"No honest pony!" Rainbow took to the air and smacked her front hooves together. "I mean, face it, Rares: that diamond's prob'bly either cut into four or five pieces by now or halfway to dragon country!"
The thought stabbed Rarity. To cut the Azdariz Diamond would be a travesty beyond compare, but for it to be carried off and buried in some dragon's hoard? "No." Her horn as numb as a leg slept on incorrectly, her hooves throbbing and her neck stiff, she nonetheless raised her head and looked east, the sun just sliding over the hills there. "Because I'll be going after it."
"What?"
"I have no choice."
"Are you nuts?" Rainbow's voice cut through Rarity's head like a mid-winter icicle. "It's just a rock! You can't seriously—!"
"It's beauty, Rainbow Dash." She could barely swallow, her throat felt so thick. "The purest, loveliest, most inexpressibly perfect object I shall ever see or touch. And to let that go..." Her whole body seemed to clench, and she couldn't continue.
"Wow," a thick voice said behind her. "Your friend must sure like watching the sun rise, Rainbow Dash."
Blinking, Rarity turned, and—
"Oh, hey, Derpy," Rainbow said from somewhere to Rarity's right. "Early delivery this morning?"
"You betcha!" The postmare gave a nod. "There's always somepony somewhere who needs their stuff before breakfast."
She may have continued speaking, but the object dangling from Derpy's neck, the chain much too long for a pony her size, the light of dawn catching it, embracing it, and calling forth its inner fire, that object made Rarity forget everything else around her.
"Huh." Rainbow stepped into the corner of Rarity's field of vision. "That a new necklace, Derpy?"
"Yep!" Catching the swinging chain with a hoof, Derpy held the Azdariz Diamond up, and staring as she was, Rarity couldn't miss how Derpy's eyes moved in unaccustomed unison to focus on the jewel. "I found it in the park the other day just laying in the mud! Isn't it the prettiest thing that's ever been pretty?"
"Yeah, I guess." The indifference in Rainbow's voice shocked Rarity; she turned to glare at Rainbow, but the glare Rainbow was already aiming at her made Rarity's simply deflate. "Not the sorta thing I'd, y'know, leave my friends and family and business and life behind to go chasing after, sure, but yeah, it's pretty enough."
Derpy was blinking at Rainbow, her eyes drifting in opposite directions again. "What?" she asked.
"Stones like that," Rainbow said, but her attention stayed fixed on Rarity so intensely, Rarity found that she couldn't look away. "You gotta be careful with 'em 'cause they sometimes make ponies do stupid things. Especially when those ponies forget the stuff that's really important."
The suit around Rarity was getting warmer and warmer, the now-risen sun shining full upon her. But a part of her mind had already begun planning her visit to Derpy's house after midnight tonight—Derpy didn't lock her doors, Rarity was certain, and the Mare-Do-Well costume should serve quite nicely to stop any hair or hide traces from remaining behind....
She shook her head. Then, just to be certain that those thoughts had been properly banished, she shook her head again. "Yes," she said, her voice barely sounding like hers even to her own ears. "It is a lovely stone." Sitting, she reached up with her hooves and removed her hat and mask. "If you like, Derpy, I can show you a better way to wear it."
"Oh, wow!" Derpy's eyes went wide even though one of them was pointing straight up. "I didn't know it was you in there, Rarity!"
"It very nearly wasn't." Rarity glanced at Rainbow and saw her friend give a real smile for the first time in many long hours. "But you need to wear a stone like that close about your neck: these sorts of gems love to rest against the skin, you see." Sparking her weary horn, she sent her magic out to bunch the chain, form a temporary clasp, and draw the Azdariz up to nestle against Derpy's breast, the mailmare's gray coloration the perfect background for the rainbows dancing within the diamond.
"Wow." Derpy whispered it this time, the entirety of her usually wandering gaze again coming together to fasten on this most singular of items. "You're right. It's even prettier now..." And the awe behind her words reminded Rarity of something else about which she was rarely mistaken: the way that true beauty could never be possessed but only shared.
Rarity took a deep breath. "Come by the shop later, and I'll fix it more permanently for you." She blew the breath out. "It'll be a lovely heirloom to pass on to Dinky someday."
"Okay!" Wings buzzing, Derpy swooped over to give her a quick hug. "Thanks, Rarity! I'll see you! You, too, Rainbow Dash!" She zipped off toward the post office, and while Rarity hadn't spent a great deal of time observing Derpy in flight, the postmare did seem to be progressing in a rather less careening fashion than she often employed.
Dawn continued its silent stirring around them for a moment, then Rainbow said, "I'm not gonna ask if you're okay, Rares, 'cause I know you are."
"I will be, I think, yes." Looking at Rainbow Dash, Rarity couldn't help recalling the one matter about which she was never mistaken: the true and unwavering support of her friends when adversity was prodding at her with its slovenly hooves. "Thank you."