"Magic crystals allow us to overcome this issue. Forgemasters and Alchemists both consider a crystal as a beating magical heart in search of a body. The more powerful the gemstone, the greater the number and quality of enchantments it can sustain.
"That is also the reason why Alchemical tools mostly use up to yellow gemstones, because it would be a waste otherwise. Alchemical tools are meant to be cheap and mass produced.
"Using green crystals or above for a single spell would defy everything Alchemy stands for. The cost of the gemstone alone would be enough to buy a better Forgemastered item.
"Embedding a crystal is a delicate and irreversible process in Forgemastering. Once the heart has a body, they become one. If the iron sword of my previous example were embedded with a green crystal, its innate magic would raise to one thousand.
This means that we can now infuse into it a magical force up to ten thousand. It makes it possible to imbue the sword with multiple spells."
"How does a crystal fix the problem of the limited time window for enchanting an item?" Asked a chestnut haired boy.
"Once one or more crystals are embedded, the Forgemaster no longer channels their magic directly through the object, but through the gemstones instead. They are also amazing magical conductors that widen the time window from a few seconds up to a few days, depending on their strength.
"Otherwise it would be impossible for a single Forgemaster to have enough mana to imbue so many spells at once. Another reason for using mana crystals is because they are a power source.
"If you remember, the elemental weapons you crafted during the past third trimester, can be only used two, three times a day tops. Gemstones allow using multiple spells in a short time frame with no mana expenditure from the user.
"Good magical items, like your communication amulets, require one blue gemstone minimum. Blue and violet gemstones are expensive, but they absorb mana very quickly from the environment, making it possible to keep an enchanted item active almost indefinitely.
"Green and cyan crystals are employed only for making toys or ceremonial weapons. Any more questions before we move to a practical demonstration?"
Lith raised his hand while Solus left his finger to take a closer look at the students. Her mana sense perceived a familiar sensation, but it was too faint to recognize it from a distance.
"Does it mean that crystal embedded Forgemastered items can last forever?" Lith’s question was linked to Solus’s nature.
’What Wanemyre explained doesn’t make sense. Thanks to true magic I know that without the imprinting from the mage, the mana pathways fade away with time and the pseudo core dissipates. If crystals are also power sources, why Solus almost died?’ He thought.
"I would have talked about this before we studied constructs, like golems or gargoyles. No harm in moving a little ahead of time, though. The answer is no, they don’t. Most stories about heroes finding legendary equipment laying on the floor are just stories.
"Without a user, an artifact will degrade over time, magical gemstone or not. It happens because all items have passive properties that are always kept active, like weight reduction, self repair, or enhanced resistance.
"Usually, the more powerful the artifact, the more passive abilities it has. It means that magical gemstones alone cannot keep up with the mana expenditure. That’s why golems require arrays that serve as recharge pods.
"Unlike artifacts, arrays have a single function making them easier to preserve. Ancient noble households are protected by several arrays, but each one has its own magical stones and requires maintenance. Anything else?"
Lith shook his head.
’The tower from her memories was so big and powerful that probably it would have required a whole crystal mine to keep it active. Especially since Solus cannot go in stand by mode. It would mean her death.’
By the end of Wanemyre explanation, Solus had returned.
"Yes." Asked a black haired girl. "Why not just enable passive abilities to be turned off whenever the object is not imprinted?"
"Because most of those spells are needed to preserve the magical item. Even if you do not notice it, imbuing an object with a great magical force causes a constant erosion. If an artifact sustains too much damage, it loses all its magical properties.
"The only way to preserve it from the passage of time is either to pass it to a new owner or use an array. Both solutions require for the original user to die in a manner convenient enough to allow for the artifact to be preserved. Useless to say, it doesn’t happen often."
Then, Professor Wanemyre proceeded to teach them the Bonding spell before giving a practical demonstration. She placed an amulet and a green gemstone inside a magic circle entirely made of runes of power. They were so tightly packed to almost resemble a straight line.
"I hope you learned to use water magic well, or drawing this kind of circles will take you days." Wanemyre grinned seeing many quivering at her words.
She didn’t need to charge the magic circle with mana. Wanemyre directly chanted instead.
The amulet and the gemstone started to float in mid air, orbiting around each other like twin stars while the runes turned into threads of blue light. The threads pierced both items, passing through them over and over again.
After each passage, the amulet and the crystal neared each other until they came into contact. Then, Wanemyre chanted a different spell. The threads entered inside the gemstone, painting it blue before spreading to the whole surface of the amulet.
Lith could see the lines of power even without Life Vision, finally understanding why crafters considered magic crystals like living hearts. The threads had formed the equivalent of a mana circulatory system, allowing the gemstone to fill the amulet/body with its power.
The lines turned from blue to green before disappearing, while the amulet returned on the flat surface of the black Forgemastering table.
’It’s just as she said.’ Solus was amazed. ’I can see with my mana sense that the amulet has now a powerful magical aura. In a way, it reminds me of ourselves.’
"Now the amulet is ready to be enchanted. The use of the Bonding spell does not imply the need to imbue spells right off the bat. Bonding and Forgemastering can be considered two separate processes.
"Now it’s your turn to try. This is tier five magic, so remember that the spell requires from you to generate as many threads you can control. The greater the number, the better the Bonding. A Forgemaster like me can generate one thread per each rune.
"In your case, since it’s your first attempt, one out of four runes can be considered a passing grade, but only if the Bonding is successful. All the threads must always go through both targets. If even one misses, the spell will fail. Who wants to go first?"