Completely unaware of Lith's inner turmoil, Professor Nalear continued her explanation.

"Red, orange and yellow are cla.s.sified as low grade crystals. These crystals are the most cheap and common. They hold the smallest amount of mana and once it's consumed, they crumble to dust.

They only have a limited number of uses as mediums for Wardens' and Alchemists' most simple creations, while they are useless to Forgemasters."

- "Cheap?" Lith was stunned by Nalear calling something worth dozens of gold coins cheap.

"My staff runs on a red crystal, and so did Yurial's array during the second exam. Even he was reluctant consuming one. I'd better ask him for explanations later."–

"For example, red ones can be used to prolong the duration of an array or to grant its control to someone different from the caster. In the former case, the Warden places the crystal inside the formation, giving it an extra mana reserve.

"In the latter one, the Warden sets his imprint on the crystal while conjuring the arrays. This allows whoever holds the crystal to turn them on and off. Red crystals are considered to be 'dumb', since despite being imprinted, anyone can use them, even against the Warden's will.

"Orange and yellow crystals work the same way, but contain much more mana and are a little 'smarter'. They can be imprinted multiple times, but only with the consent of the original caster. This makes them thief-proof, but using them for a one time array is like using a fireball to kill a fly."

The red, orange and yellow stones disappeared in her dimensional amulet.

"This leaves us with the good stuff. Green and cyan crystals are cla.s.sified as middle grade. They are used by Alchemists only for their most powerful creations, while they are much more important for Wardens and Forgemasters.

Middle grade crystals not only contain a much bigger amount of mana, but they are also able to self recharge over time. As long as they hold even a tiny speck of energy, they do not crumble.

The recharging process can take hours, days, or weeks depending on the size of the crystal and its purity. A deep cyan stone recharges slower than a bright one, the more vibrant the colour, the purer the gemstone is."

The number of a.n.a.logies between mana cores and crystals was making Lith's head spin.

"Thanks to this property, Wardens can use them to make their formations semi permanent. Fueled by a sufficient number of crystals, a defensive array can remain active always, since its mana expenditure is covered by the crystals that recharge themselves non-stop.

"Of course, the more damage the barrier sustains, the more mana is consumed, until the array is deactivated either by the magician himself or because all the crystals have been consumed

"Forgemasters can instead embed them into their creations. Thanks to the magical gemstones, items not only become able to receive multiple powerful enchantments, but also gain a mana capacity of their own, allowing their wielder to use spells that he doesn't know or that he wouldn't be able to cast at all."

Nalear took out what seemed to be a miniature sword, little enough to fit the palm of her hand. One second later, it grew to the size of a long sword, with two s.h.i.+ning cyan gemstones on its hilt.

"This is Professor Wanemyre's most recent creation. For those who don't know her, she is our best resident Forgemaster. This sword has been enchanted with multiple spells that allow it to shrink, to be sharper and st.u.r.dier than normal.

"It also allows its wielder to summon a protective barrier and cast tier three lightnings, even if he/she isn't a mage at all. It's all made possible only thanks to the mana crystals. Aside from special materials, most inorganic matter crumbles if imbued with too much magical energies.

Only mana crystals can harness such power, even managing to use the conflicting energies deriving from the multiple spells to recharge themselves faster."

Thinking about all the precious materials and resources he had wasted until the previous day, just to discover the same things he had learned in the last half an hour, Lith didn't know whether to rage or cry.

- "Random really hates me! Why couldn't this lesson have happened a month ago? I hate Professor Wanemyre so much right now. If I still had her gift, the silver plated hammer, I would bash it on her head!"–

Lith raised his hand to ask a question. Nalear noticed it and gave him permission to speak.

"I'm specializing in Forgemastering, why I have never heard about this before?" The pain resounded from his wallet up to his voice.

"Because embedding magic crystals and infusing multiple enchantments is something you'll learn on the fifth year, after you have pa.s.sed this subject and learned how to refine and handle the crystals." She replied with a warm smile.

"We have already studied how to apply more than one spell though. The Professor had us trying and failing again and again. With all due respect, but it's unfair to us students." Many colleagues from Forgemastering nodded.

They also had spent a lot of time, effort and money in a fool's errand, just like Lith.

"It's unfair to the students, but fair to the academy's budget. This way Wanemyre knows who have worked their hands to the bone gaining solid foundations, and who instead have relied on tips from their families in violation of the academy's rules."

Looking at those who had remained indifferent to Lith's lamentations, her smile turned into a grin.

"High quality magic crystals are really expensive. We can't afford you students wasting them while taking your baby steps as Forgemasters. It was her way to separate the wheat from the chaff and save a lot of her budget.

Two birds without even a magical stone." She winked at Lith, who contrary to her expectations instead of turning red became pensive.

- "Solus, is it me or Professor Nalear is a bit strange?"

"Yeah, flirting with a student is really going overboard. All those smiles and winking…" She replied with more than a tinge of jealousy in her voice.

"Not that. Look at the sword, she's holding it with one hand."

"It doesn't mean much. Maybe it's just enchanted to be light too."

"Then explain how does she know about the conflicting energies of multiple spells? She isn't a Forgemaster and even if she was, they know nothing about pseudo cores. We learned about them only because of Invigoration."

"By my maker! Are you implying she is an Awakened one?" Solus was shocked.

"It would explain her trick on the first day that seemed so similar to spirit magic, her strength and knowledge. What does your mana sense perceive?"

Solus focused all her attention on Nalear's mana core, ignoring her long legs, the full lips and the wavy hair that p.i.s.sed her off beyond reason.

"Her mana is still, just like that of a fake mage. Now that I think about it, though, the Marchioness had a magical item s.h.i.+elding her core from detection. Maybe Nalear has a similar device."

"Or maybe she has learned how to control her mana flow. I can't ask Nalear if the sword also has a weight reducing spell, it could tip her off. I'll ask Professor Wanemyre as soon as I see her."–

After the enraged chattering of the students died out, Nalear made the green and cyan gem disappear before resuming her explanation.

"Blue and violet are high grade crystals. Only the best and richest Wardens and Forgemasters can afford them. The white ones are a tier of their own, you'll never see them outside of the royal palace or powerful artifacts.

What sets high grade crystals worlds apart from their lesser cousins, is that beside the ability to recharge at great speed over time, they can also be manually recharged. Take the academy, for example." She waved at the wall, pavement and ceiling.

"The reason why even the canteen can use Warp Steps to deliver you your meals is the same that makes this castle an impregnable fortress. Not only it has been built with countless crystals that empower all of its spells and arrays.

It is also able to feed on the mana of its residents in case it needs some extra juice. Every time we practice magic, make a call with a communication amulet or activate a dimensional item, the academy takes its toll in the form of a minuscule fraction of the magic employed."

The students gasped, looking at their hands like expecting to find fleas under their clothes.

"It's at the same time a sword and a s.h.i.+eld. A s.h.i.+eld because it protects us all from internal and external threats. A sword because whoever doesn't wear a uniform can have their mana sucked dry in an instant.

Whatever spell an intruder could use, the castle would throw it back at him tenfold.

Oh, right. Only gemstones from blue and above are capable of sustaining complex functions, like projecting holograms, copying doc.u.ments and such. That's why all your communication amulets have a blue gemstone embedded and are so expensive."

At the thought that Wanemyre had showed him the blueprint for the amulet without explaining anything to him, Lith felt the desire to make the Professor and her present have a violent encounter grow even stronger.

"In the following lessons I'll teach you how to cut a mana crystal according to its intended function. How to check its quality, how to identify its consumption rate and if it has it, the recharge rate.

The last part of our lessons will be about how to manually recharge high quality crystals, with a trip to the mines in the forest to show you how to find, dig and extract raw crystals without having them explode in your face. Dismissed."

As soon as Nalear had finished speaking, the gong signalling the end of the lesson resounded and she left the cla.s.s.

"This lesson made me feel dirty poor." Lith sighed.

"I know, with my weekly allowance I can barely afford a few red mana crystals. That's why I don't use them unless it's absolutely necessary." Yurial sighed along, showing Lith a small bag containing enough red gemstones to fuel Lith's staff for more than a year.

Suddenly Lith felt the urge to gift him with a hammer too.