A passage from Morgoth's Ring implies to me that Nerdanel and Fëanor first met while they were wandering Aman. I wanted to explore that a little bit.
I own nothing.
The mingling of the Lights has just ceased, and Laurelin's golden light crests the hills and gilds the high, swaying grass. Fëanáro stands at the dusty crossroads, holding the reins of his horse in his hands, and he frowns, not exactly sure which way he's supposed to go next. Fëanáro has not seen a tree in nearly two days; that, above all else, confirms to him that he has certainly reached the region of Aman known as the Pastures of Yavanna. The one he seeks certainly lives further to the south. But none of the routes Fëanáro could take will lead him south, and he can not say how far off-course any one of these roads could eventually lead him.
When it was offered to him, his father had warned him that an apprenticeship under Mahtan the smith would entail labor and toil. "If I know Mahtan, he will press you hard. He will not go easy on you because you are the son of a King; for that very reason, he will challenge you even more greatly than he would have were you someone else's son."
Fëanáro understood that, and told Finwë quite confidently that he would endure any labor and toil that was put in his path. For was he not his father's son? How could he do anything less, but surmount all the mountains that were put in his path on the way to mastery of stone and metal-craft?
Indeed, Fëanáro was not afraid to work hard. But he thinks he may have finally met a task that, while it shall not defeat him, may at least prove successful in flummoxing him for a while.
Not two weeks ago, Mahtan finished a commission for a client living in the far south of Aman, and tasked Fëanáro, the youngest and least of his apprentices and assistants, with delivering it to his client. The commission in question is nothing particularly valuable or fragile; just a few household items, eating utensils and so on. However, Fëanáro had begun to chafe (just a little) at being kept in one place for months on end, and he leapt at the chance to travel across Aman.
And now, Fëanáro is lost.
He strokes the smooth, velvety nose of his horse, an elderly brown mare unwilling to travel at speeds much greater than a few miles crossed per hour. "I don't suppose you know which way to go, do you?" he asks her quizzically. Normally he wouldn't be seen conversing with beasts (Fëanáro is well-aware that he has no talent in such fields, and does not waste his time trying to get blood from stones), but he's lost, they're alone, and it's not like he has anything else to lose.
Just as he is resolving to cut across-country and keep heading due south, road or no road, Fëanáro picks up a faint trailing note of song. Despite himself, Fëanáro feels a sharp stab of relief in his gut (He will not let it show on his face). That sound can only mean that he is about to encounter a fellow traveler, one who hopefully knows the best road to take to get to the settlement in the far south of the Pelóri mountains.
There does indeed come another traveler, on foot, from the northeast road—or southwest, depending on how you wish to look at it. Fëanáro stares at the Quendë who approaches the crossroads, frowning slightly.
Fëanáro is, himself, thirty-five years old, and though he has often been told that he looks far older than his actual age, he knows that he has yet to reach anything approaching an adult's height. This traveler, shielded from the worst of the heat by a light blue cloak, is no bigger than he is; he thinks they may be smaller, actually. Another child, then?
Why, yes, the traveler is another child.
A girl around Fëanáro's age, to be exact. Tall like him, with long, lanky limbs and dark eyes, and who seems to have dispensed with anything resembling properly feminine attire—the girl instead wears a tunic and trousers. Her hand is curled around an oak staff, and when she sees him, she stops singing and nods to him, smiling slightly. "Good day to you."
Fëanáro can muster no such greeting. His attention has been caught entirely by her long, frizzy, very red hair.
"You're Master Mahtan's daughter!" he blurts out, all attempts at princely dignity forgotten.
She raises her eyebrows, that slight smile growing into a humored one. "Yes, I'm her. Nerdanel, if Papa hasn't bothered to tell you my name, or Istarnië, if all you've heard of me comes from Mama. Who are you?"
As a matter of fact, Mahtan has made Fëanáro aware of Nerdanel's name, though in all of the months he has apprenticed under the smith, he's never seen his master's daughter. He and all of Mahtan's assistants have been instructed to keep a weathered eye out for her; evidently, Nerdanel is a master wanderer, and tends to be away from home for longer periods of time than her parents would like. Personally, Fëanáro can't help but think that if Mahtan and Istamë are letting Nerdanel wander Aman at will, they can not possibly be too worried about her coming to harm in the wild, but he does as Mahtan commands and keeps a weathered eye out for his mentor's daughter.
So this is her.
"I am your father's apprentice," Fëanáro introduces himself at last, nodding his head and feeling uncharacteristically awkward. "I am Curufinwë Fëanáro."
"I've heard of you." Nerdanel looks over his shoulder at the mare with her packs, and she smirks. "Is Papa having you run errands for him?" That does smart just a bit, her phrasing, but before Fëanáro can respond (retort), Nerdanel asks him, "Where are you going?"
The eager tone she takes at 'where are you going?' washes away any irritation Fëanáro feels at being reduced to an errand-boy by her speech. He's not sure how exactly it did, but it has. "I'm trying to get to Amun Rusca in the far south." Fëanáro pauses a moment, not sure that he wants to expose his indecision to Nerdanel, considering how likely she is to report it back to her father, but eventually his need overcomes his pride. "Do you know which of these roads would lead me to my destination?"
She shakes her head, quite thoroughly unconcerned. "No."
Fëanáro's shoulders sag in spite of himself. "I will have to cut across-country after all," he mutters to himself, staring down the fields of grass dappled intermittently with red poppies. How long, he wonders, will it take for him to find another road, once he leaves this one?
He is drawn sharply out of his musings by Nerdanel's hand lighting on his arm. Fëanáro turns around to find her staring intently at him. "I wouldn't do that if I were you, Fëanáro. It's easy to get turned around out here. That's not so bad if you're not going anywhere in particular, but you have somewhere to be, don't you?"
"What do you suggest I do, then?" Fëanáro snaps at her, gesticulating at the roads.
She shrugs, and smiles, but it is a smile without any of the mischief of a smirk, and Fëanáro is caught off-guard by it. How can he not be? "Pick one of the roads, the one that goes southeast, or southwest. Then, we walk."
"We?"
"Yes, we."
Nerdanel points with her staff at the two roads she specified, first at southwest, then at southeast. She stands there, the wind buffeting her hair back and forth, trying to decide. Fëanáro stares at her back, wondering exactly what must be going through her mind. Then, she seems to decide on southeast, for that is the road her feet lead her to.
Fëanáro can really do nothing but follow her. If they get lost, at least he won't have to sit warming his hands by a campfire at the side of the road with only the mare for company.
She's more interesting than I thought she would be.
Fëanáro, Curufinwë—Fëanor
Quendë—Elf (plural: Quendi) (Quenya)