After telling these Dan Dao secrets, the little guys below were as serious as listening to the story, completely focusing on Elder Xu's body.

Seeing that he had achieved the effect he wanted, Elder Xu finally began to explain the first theoretical knowledge of alchemy, that is, the theory and techniques of elixir purification.

It turns out that for the elixir, the inside of each elixir contains the unique essence of this elixir, and when they absorb the aura of heaven and earth, they will refine the aura into their own essence in a special way and hide it in themselves.

The more aura the elixir absorbs, the purer the essence it conceives, so the elixir will become more precious the longer it ages.

When alchemy, the alchemist is to take out the essence of the elixir, and fuse and condense these essences in a certain way, so that the zuihou can form the elixir.

As for the elixir, the essence is hidden all over the body, not like human monks, who hide the absorbed spiritual energy in the dantian after refining it.

There is no dantian for the elixir, and if you want to extract the essence of the elixir, you have to think of other ways, and this method is to use fire to extract the essence of the elixir.

The elixir itself is divided into two parts, one is the essence that is useful for alchemy, and the other is the dross that is useless for alchemy.

The process of purifying the elixir is the process of removing the turnip and preserving the essence, and in the elixir, the essence part and the dross part will generally have a different degree of fire resistance.

Because the essence part has been accumulated and tempered by spiritual energy, the ability to resist fire will be higher than that of the dross.

When purifying the elixir, it is necessary to precisely control the temperature of the flame so that the temperature of the flame can burn the dregs of the elixir to ashes without harming the essence of the elixir.

This is extremely difficult for a monk who is new to alchemy, because the temperature of the flame is rarely different, and the elixir will be destroyed.

If the temperature is not enough, there is no way to burn the dross, and if the temperature is too high, it is easy to burn the essence, so the purification elixir is extremely testing a person's control over mana, and only if you can control your mana very well, can you control the temperature of the flame.

This is only the most basic skill, when becoming a true alchemy apprentice, you must also be able to separate the dregs of the elixir that burned into ashes from the essence, which tests the divine sense and mind.

Without a strong consciousness, there is simply no ability to distinguish between the essence and the dross, and without a firm mind, there will not be enough patience to separate the essence from the dross little by little, and this process of separation is even more tedious than peeling back the cocoon, so patience is also very important.

This is only the level of an alchemy apprentice, if you want to become an alchemist, you must have the ability to differentiate and control the divine sense, when alchemy, it generally does not contain only one elixir, even the simplest elixir will contain several elixirs.

These elixirs converge in a pill at the same time, and the flame temperature required to purify these elixirs sometimes varies a lot, and it is not possible to use the same temperature to achieve the effect of purifying all the elixirs, which requires the alchemist to be able to control these elixirs in different areas of the pill at the same time.

And in different areas, the flames are also at different temperatures, so that these elixirs can be purified at the same time.

Or first put one elixir into the pill, purify one, and wait for the current elixir to be purified, and then continue to put another elixir and purify the next elixir, but this method is inferior, and it is worse in terms of alchemy efficiency and success rate.

Although such an alchemist is also an alchemist in the eyes of ordinary monks, in the eyes of an alchemist, no matter how high his achievements are, he is not recognized by his peers, saying that such an alchemist is not a real alchemist, and such an alchemist generally has extremely limited achievements, and he will not have too high attainments in the path of alchemy.

This is the reason why some alchemists in Weishenme put all the elixirs into the Danding when they were alchemizing, and then ignited the fire and started alchemy, while some alchemists put the elixir into the Danding in the same way.

For beginners in alchemy, it is better to use the latter method, after all, they are not alchemists yet, they are just alchemy apprentices, so no one will laugh at them.

Elixirs are not easy to come by, and it is still haode to destroy less, only after purifying a lot of elixirs and mastering the purification laws of elixirs, before starting to practice and purifying a variety of elixirs at the same time, that is the only way to go to the Dan Dao master.

For alchemy apprentices, another factor that measures the level of alchemy is the degree and quantity of elixir purification.

The essence of the elixir and the dross are mixed together, so it is very difficult to purify, and sometimes it is difficult to separate the essence and the dross, and there will inevitably be some trade-offs.

Whether to keep the essence mixed with impurities, or to discard the impurities mixed with essence, on the one hand, to ensure the amount of essence left, and on the other hand, to ensure the purity of the essence.

It is difficult for beginners to choose, most beginners will be reluctant to Lang Fei Ling, retain the essence mixed with impurities, such a result is that due to too many impurities, the quality of the refined pill is unsatisfactory, between the finished pill and the waste pill, it is a pity to discard it tastelessly.

And the experienced alchemist will give up these impurities mixed with the essence of the elixir, although this can ensure that the elixir becomes a finished pill, but the spiritual power contained in the elixir is not satisfactory, and it is also an unsatisfactory work, so although the purification of the elixir is only the most basic skill of alchemy.

However, this skill is the foundation that determines how far you can go on the path of alchemy, and practicing the basic skill of elixir purification is an indispensable part for monks who want to become alchemy masters.

After listening to Elder Xu's explanation, Xiao Yu felt as if he had been empowered, and his heart suddenly brightened, and he finally understood that the alchemy tips mentioned in Weishenme's later volume did not explain much alchemy skills, but talked about a lot of skills when the elixir was purified and the skills of flame control.

There were even a lot of Dharma decisions for exercising divine sense, and the technique of divine consciousness differentiation was also mentioned, and Xiao Yu was still ignorant when he saw this.

Alchemy experience, what are you doing with so many elixir purification techniques! It turns out that the purification technique of elixir is so crucial!

No wonder all the alchemy experiences are emphasizing the skills of purifying the elixir, it seems that those alchemy experiences are really not nonsense, and I will study it in the future.

After Elder Xu finished talking about these theories of elixir purification, he began to explain the techniques of purifying elixirs, which was actually not a skill, but a safe method.

That is, when purifying an elixir that you are not familiar with, at the beginning, the energium increases the temperature to the lowest, and then raises the temperature little by little, and always pays attention to the changes in the elixir.

When the elixir itself begins to change and impurities begin to appear, it is necessary to stabilize the temperature of the flame and begin to separate the essence from the impurities.

Until the separation is completed, if the elixir has reached the level of purity it needs, it can be fused with other elixirs and proceed to the next step.

If you feel that the elixir can be further purified and refined, then continue to increase the temperature of the flame on the original basis, and then continue to separate the impurities and essence until you get the elixir essence that you are satisfied with.

In fact, this is the same as the principle of refining, when refining the tool, it is also necessary to refine the raw materials through thousands of hammers, remove impurities and refine the essence, and the purification of the elixir is also a process of thousands of tempering, and it is not a one-time completion of the purification of the elixir.

Of course, those experienced alchemists have already purified thousands of elixirs, so they have long been familiar with the medicinal properties of elixirs, and they can raise the temperature of the flame to the limit that the elixir can withstand in the fastest way, so that the process of refining the elixir will be very fast and of high quality.

Xiao Yu was already fascinated by these theories, and before he knew it, two hours had passed, and today's lesson had ended.

Elder Xu has already enjoyed himself today, he has already explained all the theories and techniques of elixir purification, and these disciples below still need to digest the knowledge they have learned, and then it will be harmful to them.

Elder Xu stood up a little reluctantly, and said loudly: "Little guys, that's all for today, practice more after you go back, come back in three days, and disperse!"

After finishing speaking, he walked out of the hall first and disappeared, not even paying attention to the disciples saluting.

After Elder Xu left, Xiao Yu walked out of the alchemy hall step by step as if he had drunk three catties of old wine, and he didn't even notice that the little girl with an ethereal aura next to him was talking to him.

Zuihou didn't even know how to get back to the cave mansion, because he was now completely immersed in the way of alchemy explained by Elder Xu.

He sorted out and analyzed every theory he learned today, memorizing it as he went, for fear that he would accidentally forget a little.

In fact, when the Yuanshen realm reached Xiao Yu's level, it was not difficult to remember some things, but it would be even more difficult to forget some things, but he regarded the alchemy path he learned today as too important, so he was so nervous.

It wasn't until he had combed through all the alchemy techniques he had learned today, and was sure that he had mastered them, that he came back to his senses.

Suddenly found that Xiao Jiumei was standing in front of him, looking at him strangely, and her face was almost on his face.

Xiao Yu was startled, and hurriedly jumped back, but he didn't want him to stand on the edge of the wall just now, and this jump happened to hit the wall, and it was called a solid one.

Xiao Yu said "oops", feeling that the bones were about to fall apart, Xiao Jiumei saw that Xiao Yu had finally returned to her soul, so she said teasingly: "Oh, which fox spirit hooked your soul to, and now you are willing to come back!"

Xiao Yu didn't have the heart to play with her, and now he wanted to practice the alchemy he had learned, so he hugged Xiao Jiumei and kissed her hatefully on the face to show comfort.

Then he said: "Good, don't make trouble, it's very difficult to learn alchemy today, I have to practice well, otherwise I can't learn if I can't pass the test, and I will be playing with you when I have time, obedient!"

After speaking, he rushed into the alchemy room with a few spirit grasses in his arms, and began the first step of walking into the alchemy master.