Chapter 121: 120: Glassmaking (Fourth update upon release, please subscribe!)

Richard was unaware of the incident at the jewelry store, but after obtaining the ruby, he had finally gathered all the ingredients necessary for making Cobalt Blue. The next step was to produce the Cobalt Blue itself, followed by crafting the actual Cobalt Blue Glass. Thus, Richard and Gro headed to their final destination for the day—the Glass Factory in the Jade Kingdom.This place was not one that just anyone could enter, not even Gro could come and go as he pleased.

This was mainly because glass, especially high-quality glass, in the current world, similar to the Medieval era, was considered an absolute luxury. Large sheets of glass mirrors cost more than gold, and the small pieces of colored glass used for church window decorations were also of considerable value. Even broken glass shards were not something ordinary people could obtain, often coveted by Noble ladies to be inlaid into their sumptuous evening gowns to wear to dinner parties. In their eyes, broken glass shards were more radiant and representative of status than any gemstone rings or pearl necklaces.

Simply put, civilians almost never came into contact with glass; it was entirely exclusive to the Nobility and involved enormous profits. For this reason, a country would tightly control its Glass Factory, placing it in a remote location, guarding it with heavy soldiers, and craftsmen were not allowed to leave the Glass Factory for their whole lives, to prevent any leakage of their techniques.

In fact, this was also a true reflection of modern Earth’s history.

In Earth’s history, around the twelfth century, Venice—as the glass manufacturing center of the world at that time—kept all glass artisans confined on an island known as Murano Island for several centuries, to monopolize glass-making techniques.

In the current world of the Jade Kingdom, things had not reached such an extreme, but Gro had used his status as a Prince and went through much trouble to finally obtain permission to bring someone into the factory.

After several identity checks, Gro led Richard into the interior of the Jade Kingdom’s Glass Factory.

Inside the massive wooden shed, with pools everywhere, furnaces lined up, and the heat rising to the sky, a multitude of workers and craftsmen bustled about non-stop, clambering up and down the racks, with a constant din of shouting.

“Shake, hurry to furnace number one, see if it’s gone out!”

“Babes, go to furnace number four, check the fuel.”

“Nusi, there’s a problem with pool number fifteen, quickly call Master Monghaqi over…”

The factory manager of the Glass Factory—a man in his forties with brown hair and high cheekbones, named Vichis—led Richard and Gro through the wooden shed with a respectful attitude. After all, the strict security of the Glass Factory was one thing, but as the manager, he was still no more than a lowly commoner in front of Gro. If he dared show any disrespect, Gro had the authority to throw him into the pool and turn him into glass.

With such an attitude from Vichis, the process went smoothly, and Richard was soon brought to a temporarily halted melting furnace. Using some techniques, he combined the Cobalt Ore, ruby, and phosphoric acid to create the Cobalt Blue pigment.

He then handed the Cobalt Blue over to Vichis, instructing him to incorporate it into the unfinished glass in a specific ratio, ultimately producing the Cobalt Blue Glass that met their requirements.

Vichis quickly got to work, and after a short time, he brought over the product.

“Lord Richard,” Vichis offered a palm-sized sample of glass to Richard and said, “This was crafted just now according to your instructions; please take a look… are you satisfied?”

Richard took the glass sample, glanced over it briefly, and saw that it exhibited a sea blue hue, basically meeting the requirements of Cobalt Blue Glass, but…

Richard slightly tilted the glass, changing the angle of the incident light. He could see a faint green color seeping through the glass, and his brows immediately furrowed.

This was… an indication of impurities in the glass.

Richard thought.

This wouldn’t be something Vichis had done on purpose, as he neither had the courage nor the motive for it. It was purely an issue with the crafting process. In this world, similar to the Medieval era, glassmaking hadn’t achieved the modern Earth standards. They used a more traditional method, employing silica (SiO2, mainly found in quartz and sand) as the raw material for making glass.

The melting point of silica is about 2000 degrees Celsius, which ordinary melting furnaces can hardly reach. To reduce the difficulty of production, sodium carbonate (Na2CO3, also known as soda) and potash (K2CO3, potassium carbonate) were added to lower the melting point to around 1000 degrees Celsius. However, sodium carbonate caused the glass to be soluble in water, so usually an appropriate amount of calcium oxide (CaO) was also added to ensure the insolubility of the glass.

In this process, many raw materials and minerals were unable to achieve a hundred percent purity and would invariably contain some impurities, with iron being the most common mineral element to be inadvertently mixed in. Through a series of reactions, ferrous ions would be produced, giving the glass a pale green color of ferrous ions.

This was an unavoidable phenomenon unless the whole crafting process was improved and unless all raw materials and minerals achieved absolute purity; otherwise, the problem couldn’t be solved at the source.

Generally speaking, this wasn’t too much of an issue. In fact, on modern Earth, many low-cost glasses exhibit a faint green hue. Beer bottles, designed to protect beer from ultraviolet light damage, are intentionally made using iron elements to achieve a dark green color.

But what Richard was trying to create, the cobalt blue glass, was meant for conducting a flame test experiment. Cobalt blue glass needed to eliminate potential color interference to ensure the true color of the flames was observed; hence, it should ideally have no color difference.

In that case…

Richard’s brows deepened in thought. After a moment, he flipped his hand, revealing a small glass bottle in his grasp filled with half a bottle of grayish-white metallic powder—manganese powder.

Since the problem couldn’t be resolved at the source, it had to be dealt with at the final stage. A small amount of manganese could counteract the faint green tint caused by ferrous ions within the glass. However, the concentration had to be carefully controlled, as too much manganese would turn the glass from light green to light purple after the green was canceled out.

Richard handed the manganese powder in the glass bottle to Vichis, and said, “Make another batch of the blue glass pieces I need. This time, sprinkle this powder in during production. The concentration should be…”

After speaking at length, Richard looked towards Vichis, who appeared slightly stunned, and asked, “Do you understand?”

“Uh, yes I understand, but… what’s the use, Lord Richard?” Vichis inquired with a hint of confusion.

“You don’t need to worry about that. Just do as I said,” Richard replied.

“Uh, okay.” Vichis glanced at Gro, who seemed a bit bored on the side, took the manganese powder given by Richard, and went off to find someone to carry out the task.

After a while, Vichis returned with the newly made cobalt blue glass, looking very composed, but his hands were trembling, unable to conceal his excitement.