Lin Mu carefully watched the molten gold and scanned it with his spirit sense. He could feel that other than gold, there were other substances mixed in it. They were not like chunks or separate particles though and seemed to be mixed finely with the liquid gold.
"From here, I can increase the heat and let it separate out." Lin Mu muttered and increased the output of flames.
~SHUA~
Like a forge that had just been stoked with bellows, the flames directly doubled in intensity. The iron cauldron was pretty much hidden by the flames, and it looked like there was a fireball floating in the air.
The area around Lin Mu had already been dried up by now and the ground directly below the Cauldron was scorched black. The liquid gold bubbled even more and the heat continued to pour into it.
Some time passed and Lin Mu could see floating particles on top of the surface of gold.
"There we go!" Lin Mu exclaimed.
It was his first time doing it, and he had managed to remove a majority of the impurities.
'Now to scoop them out.' Lin Mu began with the next step.
He took out another tool from his ring, which was like a shallow ladle. He steeped it in the liquid gold and skimmed its surface, removing all the impurities that were floating on it.
The impurities were a mixture of colors, with the majority being black, Grey and white. Throwing the impurities to the side, Lin Mu continued heating the gold. There were still some bubbles coming from the gold and he needed to continue doing it till the gold stopped bubbling.
Lin Mu checked it with his spirit sense and saw that it was now far purer than before.
"Now for the final step… actually refining it enough to make it reduce in volume." Lin Mu muttered in a serious tone.
This step was also the most difficult part of the entire process, since it needed pressure and heat at the same time.
~clang~
Lin Mu put the lid of the cauldron on and rotated it so that it would lock in place.
This time he used both his hands and used gestures to control the heat while keeping an eye on the liquid gold inside with his spirit sense. Since most of the gases in the form of impurities were already removed, the internal pressure did not spike like it would have normally.
The volume of gold stayed the same for the time being, but its temperature kept on increasing.
"Focus… focus…" Lin Mu muttered as he increased the heat even more.
The cauldron itself started to turn red as the heat started to overcome the formations that protected it. Still, it wouldn't break just from this and it was just the temperature maintaining formation that had failed.
The durability and formation was still working and won't break… at least not now.
By the time the heat reached a new level, the liquid gold inside had change color once again. Now, it was an almost blinding white in color. The heat had reached a peak point and Lin Mu knew it was time to circulate it.
~huu~
Taking a deep breath, Lin Mu split his mind to let out spirit Qi from his hands. This time it was pure spirit Qi and was not the fire elemental spirit Qi like before. The spirit Qi was like an invisible gas and floated around his hands.
Lin Mu used a tendril of spirit sense to guide this spirit Qi to the red hot cauldron. It passed through the restraints on the cauldron and seeped through the microscopic gaps in the iron.
Then it finally reached the pool of liquid gold inside. There it wiggled its way down and formed a circular ring around it.
'Need more spirit sense tendrils,' Lin Mu realized and produced more of them.
Then controlling all of them, he grasped the spirit Qi, turning it into several individual streams. These streams then started to flow into the gold and pushed it. And since it was being done from all angles, the liquid gold started to move.
Lin Mu controlled the spirit Qi streams to make it move at a deflected angle, which then made the liquid gold move in a spiral pattern. Till this point, the process was hard and taxing, but soon Lin Mu found the equilibrium and didn't need to put as much effort.
~Phew~
"Now to just maintain this." Lin Mu said as he took a breath of relief.
The liquid gold continued to stir within the cauldron and slowly absorbed the spirit Qi into it. Bit by bit, its properties started to change and it started to bubble once more.
~STRETCH~
The sound of metal being pressured was heard as the Iron Cauldron let out a low creak. The bubbles coming from the gold had increased the internal pressure. But at the same time, it made the lid of the cauldron tighten due to the opposing force.
'Perhaps it'll be better to use an even stronger cauldron for this…' Lin Mu noted.
Since it was going to be a first try, he thought that trying from something low leveled would be better. But he was now proved to be wrong. Which was a good thing, since it allowed him to learn better.
At this point, Lin Mu was already satisfied and even if the cauldron broke, he wouldn't mind it. He had come way farther than he had originally thought for the first try.
"May as well go all in." Lin Mu said with determination and increase the amount of spirit Qi he was pouring into the gold.
~SIZZLE~
As of water was poured into boiling oil, the gold sizzled and jumped. But at the same time, it absorbed far more spirit Qi than before.
~thung~thung~thung~
The sound of gold sputtering inside the cauldron could be heard as the vessel started to sustain damage.
About ten minutes passed like this until finally, the expected happened.
~BOOM~
