Sunset decided, after requesting permission, to store her chests in Twilight’s garage, next to the Enchanter. They were too big and wouldn’t fit in her room, and she didn’t even have space to store all her books and materials. Both Night Light and Shining Armor ended up exhausted after carrying the heavy chests.

When the weekend arrived, Luna took Sunset to Twilight’s house again. Her saddlebags had become a backpack, but the contents had remained the same, which she was grateful for. She had the sheet of iridosmium she’d purchased, the book on reagent minerals Twilight had picked, and an ornate wooden box that contained her lapidary tools.

“What are those?” Twilight asked as Sunset opened the box on the little table they used to have lunch in.

Sunset turned the box around so that both could easily see the contents. “These are obsidian lapidary tools. They’re for shaping the gemstones in the exact shapes you want them. This knife, for example,” she said, pointing at the tool with the hook-like blade, “is for cutting off large sections.” She pointed at another tool with a smaller, straight blade. “This one is for small and precise cuts.” The next tool was an inconspicuous-looking flat sheet of rough obsidian with a steel handle at the back. “This is the sander for polishing the facets. And this other one,” she said as she pointed to a similar tool, except that it was slightly curved,” is the sander for polishing cabochon.”

Twilight looked at the tools with wide eyes. “I thought gem cutting needed larger, more precise tools.”

“Maybe normal gemstone cutting,” Sunset said, remembering the contraptions she’d seen in book illustrations. “But these tools were made with mana-treated obsidian.” She picked the hook-knife, feeling it heavy in her hand. “On its own, obsidian already has a low threshold, which is perfect for letting mana flow through, and is rich in both sodium and potassium, which are the best metals for mana storage. However, it has the particularity of being impervious, which means that it cannot be enchanted.”

“At all?” Twilight asked as she admired the knife.

“At all,” Sunset replied. “But, when magically-treated, obsidian becomes slightly tougher than corundum, doubled down when charged with mana. Let me show you.”

Sunset went to the chest that held her gemstones, which were inside large boxes. She picked the top box and brought it to the table. Sitting down, she opened one of the nine compartments and took out a square-shaped ruby the size of her palm. She snickered at the way Twilight’s eyes shined upon seeing the gem. Sunset gave it to Twilight and then handed her a pair of large scissors that had been lying around the garage.

“Try to cut it,” Sunset said. Twilight looked at her like she’d grown a second head. “You won’t be able to damage it. Try it.”

With hesitant hands, Twilight did just that. She timidly slashed the scissors’ blade across the ruby’s central facet. It did nothing. She tried again with more vigor. Still nothing. She placed the ruby on the table, then stabbed it. The gemstone flew away and hit the garage’s door with a loud clank before falling to the floor with several more clanks. When Twilight recovered it, she found it still spotless.

“If you know about gems, you should be aware that ruby is a corundum gemstone, which means it’s very difficult to scratch,” Sunset said, taking the ruby from Twilight’s hands. “It also happens to be really tough, which means it’s not easily broken. It’s tougher than diamond, mind you. So, no matter how much you try, you won’t be able to make a dent in it. But what if I need this particular gemstone to be half its size?”

In order to answer her own question, Sunset brought the obsidian hook-knife next to the ruby. She took a deep breath, focusing on her mana pool, then willed it to flow towards the tool. Thanks to its high sensitivity, the obsidian accepted her mana more readily than quartz, and Sunset could feel the knife getting comfortably warm. When the tool was full of energy, Sunset tilted it to an angle, then carefully slid it through the center of the ruby.

It cut it with the same ease a scalpel would paper. There was almost no resistance as the blade sliced the gem in half. In only three or so seconds, Sunset went from holding one to two rubies.

“I don’t believe it,” Twilight breathed out, eyeing the knife with a lot more caution than before.

Sunset smiled at her, then placed her thumb against the blade, chuckling at the way Twilight gasped. “It’s ok. Sure, it’s sharp, but it won’t cut me like it did the ruby. As long as you’re careful, nothing will happen to you.” She offered the knife to Twilight, who accepted it with shaking hands.

“It…” Twilight said as soon as she held the knife. “It has mana?”

“I infused it with mine. That’s why it works so well,” Sunset replied with a satisfied nod. “Without mana it would require so much effort it’d be dangerous.”

Twilight observed the knife with renewed curiosity. After a spell, she looked at the ruby halves in Sunset’s hand and pursed her lips. “Are you sure it was ok to ruin it just to show me how the lapidary tools work?”

Sunset smiled widely, having waited for that question. She reached out to the box containing the tools and removed the top shelf, revealing more tools beneath. She picked the sealer, which was a small, flat piece of obsidian attached to a handle similar to the knives. She used a hand to press the ruby halves together, then infused the tool with her mana, and proceeded to press the obsidian side against the gem, all throughout the cut. When she finished, Sunset gave the once-again whole ruby to Twilight.

“So you can just… fix them?” Twilight said as she inspected the ruby.

“Pretty cool, huh?” Sunset said. “It only works with pieces of the same gem, and only if you use it within thirty minutes of having made the cut. But it’s a real lifesaver when you make a mistake.”

“It is impressive,” Twilight said. “What are the other tools for?”

There were two more tools in the box. Sunset pointed at the first one, which was a very small, flat horizontal blade. “A chisel. It’s mostly used when you want to decorate a gemstone by inlaying it with something else. The results can be pretty, but they’re mostly useless.”

Sunset pointed at the last tool, a very sharp and thin needle-shaped piece of obsidian attached to a handle. “This is the drill. As the name suggests, you can drill holes in the gemstones. It’s not a very common practice since it’s very easy to break the gem, and even easier to just inlay it into a piece of metal. I only used it once and didn’t really like the result.”

“I see,” Twilight mumbled. “These definitely will help. I saw the way you struggled to find quartzes of similar sizes and shapes.”

“Right,” Sunset said, relieved. “And now we’ll be able to use proper reagent gemstones for the Enchanter. They should improve its efficiency at least tenfold.”

Twilight perked up. “Oh, that’s great!”

Sunset nodded. “But first, I need to document all the gemstones we have at our disposal. I brought my entire collection, but since we can’t just go back to Equestria to buy more, we’ll need to be careful not to use them carelessly.”

Twilight nodded energetically, producing a notebook and a pen, making Sunset smile. They spent the following four hours recording and documenting all the gemstones Sunset had brought, which were a lot more than she had calculated. Variety wise, her collection was pretty standard, but it made it up with quantity with well over four hundred gemstones. It was a small fortune even in Equestria, so it wasn’t strange that Twilight had become frazzled as she counted the final gem.

“Why do you have so many emeralds?” Twilight asked. The final count was well over one hundred of the green gems.

Sunset shrugged. “They’re good for practice when you’re learning how to enchant, but eventually fall short as soon as you move into advanced spells. Since I always bought gems in bulk and stopped using emeralds… Well, you see the result.”

Twilight blinked slowly. “So, do all gemstones have different properties?” She asked as she placed her pencil down.

“Yes,” Sunset replied. “Some are better for certain kinds of spells than others. Some do better as batteries. Knowing your gem is half the job for enchanting.”

Twilight nodded, then picked an oval shaped orange gem. It shined under the light, though the many tiny white dots that sprinkled it made it look like it glittered as well. “What can you tell me about this one?”

Sunset frowned as she looked at the gem. “That’s a sunstone. They’re useless.”

“For enchanting?”

“Yes,” Sunset said with a curt nod. “They’re easy to scratch and break, are very resistant to mana flow, can barely hold any arrays at all, and are even worse than quartzes as batteries. And if you ask me, they’re not even pretty to look at.”

Twilight looked back at the gem between her fingers, rolling it a few times. “Is that why you only have one? I kind of thought it was because they were super rare and expensive.”

Sunset snickered. “They’re very common. The only reason they have any worth is because of their symbolic nature towards Princess Celestia.” She felt herself sneer, then shook her head. “Keep it. It might be worth a bit more in this world, like all other gems, so sell it if you want.”

Twilight blinked a few times. “Are you sure? I-I mean…”

“I don’t want it,” Sunset said, looking away. “It’s useless anyway. Now, moonstones?” She smiled as she picked a spheric gemstone. It had a sort of milky transparency, with a soft blue luster and a beautiful luminous streak that ran through the stone’s diameter. “These are the best gemstones for batteries, especially when powered with moonlight magic. They’re also quite a pretty sight, wouldn’t you agree?”

“I… I guess so,” Twilight said with a small frown. She twirled the sunstone a few more times before she gently placed it on the table. “Can you tell me more about their properties? I want to help you as much as I can.”

Sunset cocked her head. “Well there’s the book you grabbed at the reagent store.” She took it out from her backpack and gave it to Twilight. “It’s about minerals and their magical properties. It should tell you all you need to know about the gemstones we have at our disposal.”

Twilight smiled as she accepted the book. “Thanks.”

As Twilight read the book, Sunset went ahead and started analyzing which gems would be the best to replace the quartzes of the enchanter and how to cut them for the most efficiency. She may have many gems, but just like she had told Twilight, they wouldn’t be able to get more anytime soon, so she couldn’t afford to waste them carelessly. And as she drew comparison tables and other diagrams, she took the book from Twilight on several occasions to get more complex data like impurity ratios per carat and the like.

Hours later, and after having lunch, Sunset began drawing ideas for how to improve the Enchanter. Up to this point, the machine worked entirely with quartz. Most varieties of quartz were poor enchanting materials as all their properties related to mana were worse than those of gemstones, and they tended to break quite easily under strain, both from mana and circuit complexity. So now that she had gems at her disposal, Sunset wanted to make sure all were used appropriately.

First of all, the jaspers they used for batteries had to be replaced stat. Of all the quartz varieties Sunset had been able to get, they had been the ones to retain the most amount of mana, but still they tended to lose it all in only a few hours anyway and needed to be recharged constantly. Literally any gemstone was better to work as a battery. She had told Twilight moonstones made the best batteries, but she ultimately chose one of her smallest jadeite gems, a two by one centimeter rectangular stone. It was about the same size as one of their jaspers, but it could hold about twenty-five times more mana and if left unused, it would hold it for many moons.

A moonstone of the same size would be twice better, but Sunset had very few of those. Plus, they were very fragile, and Sunset didn’t want to risk breaking them before she was sure her improvements worked as intended. Jade, on the other hoof, was very difficult to break, so there was no need to worry in case of accidents.

She had Twilight fill it up with mana.

“Oh wow,” Twilight said, wrapping her hand around the jade. “It really can hold a lot more! Why, though? Is it because of the chemical composition? The mineral impurities? The—”

“Twilight,” Sunset interrupted her with a snicker. “All of that’s in the book.”

Twilight blushed. “Right. Sorry.” She looked down at her hand as she kept filling the jade with mana.

Sunset took a break from her notes to look at Twilight’s focused frown. The way her nose scrunched up and her lips pursed as she concentrated was adorable, and Sunset thought she’d never get tired of it. Maybe she should have Twilight fill the battery every time now.

A part of Sunset tried to reject those feelings and turn them into loathing, desperately clinging to a need to vent her frustrations and sense of betrayal. But the larger and ever growing part of her preferred to simply sit back and bask in the nice warmth she felt whenever she laid eyes on Twilight. She felt annoyed when Twilight attacked her with a barrage of questions about magic, but she also liked the sound of her voice and didn’t want her to ever shut up.

Her feelings were so all over the place that the knowledge that Twilight’s counterpart had stolen her apprenticeship was at the very bottom of the pile of things bubbling up in her mind. It still stung, and Sunset would not try to convince herself that it would ever stop stinging, but she was reasonably sure that it would be worse for her if she tried to push Twilight away.

Twilight let out a sigh, a small droplet of sweat running down the side of her face. “I think it’s full now,” she said as she opened her hand, showing the jade. “That… took a lot out of me…”

“Oh, yeah,” Sunset said as she grabbed the gem. It felt relatively cold to the touch, but she could feel the unmistakable swirl of mana inside. “Jade’s threshold for mana flow is very high, which means that it won’t accept the mana flow unless you manage to overpower the threshold. You’ll get used to it with practice.”

“I hope so,” Twilight replied, leaning back on her chair with a tired huff.

Sunset knew that feeling. Making your mana flow into something with a low threshold like quartz was something that required some practice but was ultimately easy to learn and do. But making it flow into objects with higher thresholds required more force behind the flow, like trying to push a door made of steel after being used to pushing cardboard ones. Twilight would eventually develop that strength, and she’d be a step closer to being the perfect scientific partner, both knowledgeable and skillful.

“Wait,” Twilight said after recovering her breath. “If jade requires that much effort to get mana flowing, won’t it make the Enchanter work even slower?”

“Very well thought, Twilight,” Sunset replied, then picked a bright ruby from its compartment. This one was an octagon the size of her pinky nail. “That’s why we’ll be using this. Corundum has one of the lowest thresholds amongst gems, and rubies in particular have the second highest drain rate. If we enchant this one with a mana pump spell and connect it to the jade battery, it’ll easily overcome the jade’s threshold and power the Enchanter without issues.”

Twilight hummed and nodded, then smiled. “We’re using the Enchanter to create better components for itself. It really does feel like we’re making progress, huh?”

“Definitely.”

“Do you remember the arrays for that mana pump spell?” Twilight asked. “How long will it take for you to add them to the Interpreter?”

Sunset smiled. “I don’t think I remember them completely. But that’s why I brought all those books.” She walked to her chests and rummaged through them until she victoriously lifted the book she was looking for. Upon returning to the table, she gave the book to Twilight.

“‘Enchanting for Novices. All the spells you need to know to start the journey through the wonderful world of enchantments’.” Twilight finished reading the title and proceeded to immediately open it. “Oh, the light producing spell is the second one!” She flipped through the index. “Ah, here it is! Page one hundred and twelve.”

Sunset couldn’t help but snicker as Twilight flipped the pages with a determined look. Her chest and face warmed up, and though they certainly felt comfortable, Sunset didn't hate it.

She still wasn't sure what she wanted to do going forward. Working on the Enchanter was just something to keep her occupied, but she really needed to settle on a real objective. But before that, she had to decide whether she'd return to Equestria or not. There were many downsides, considering that her reputation was tarnished by Celestia ending her apprenticeship, and she most likely had a warrant for her arrest for attacking royal guards and infiltrating the palace.

Even if the princess gave her a pardon, which Sunset highly doubted, there wouldn't be many places that would hire her as a sorceress, and so all her studies had been for naught.

On the other hoof, the human world was inconvenient in all sorts of ways. The weather behaved on its own with no real schedule. The food wasn't very tasty. Her human body was all sorts of uncomfortable, what with the lack of fur to keep her warm, or the lack of a horn for spellcasting! She was planning on building a prosthesis of sorts, sure, but there was no guarantee that it would work like she wanted.

If she thought on the flip side of things, the human world offered the possibility that had been denied to her in Equestria; she could become forever recognized in the history books as the one to ‘discover’, study, and apply magic for technological purposes. Her name would be synonymous with greatness and scientists would study her notes for generations. There was a legacy for her to build. Plus, she couldn’t deny the fact that, despite strangely conflicting feelings in her stomach at the thought, she had people who cared for her in the human world. And of course, Twilight was there as well.

Equestria, however, was a world of magic. Weather was controlled properly, food was actually good, she had a horn, and she knew what to expect. And despite everything, it was still her home.

It was a tough decision to make. But, well, there really was no rush, was there? She had a whole thirty moons to think. For now, she could just rest her head on a hand and quietly watch Twilight as she read a book.

Author's Note

You would not believe the amount of research that went into making this chapter. I spent many, many hours reading about gemstones and minerals in wikipedia and other gem related websites, and I watched several videos as well.

I made a list of a some gemstones detailing all their information, both physical and magical, and I made a list of concepts. If you want, I can copy those lists in this author's notes or somewhere else. But for now, I hope the explanations within the story proper are enough. I'd like to see if you can guess the logic I used regarding the properties of the gemstones Sunset describes this chapter!

If you liked it, please leave a comment!