After many purification treatments, the ground fire will basically be very stable. It can even be compared to a charcoal fire.

When it comes to charcoal fire, we have to introduce it.

There are many types of charcoal fires, and the worst is charcoal, because the temperature is limited, and the maximum is about 700 degrees. And it's easy to burn out. You need to keep adding new charcoal to the stove.

Adding new charcoal to it will definitely cause the fire temperature to be unstable.

The people of this world are very clever and after many generations of hard work, they invented the bellows. The charcoal can be burned quickly by blowing air. Solved the problem of unstable fire temperature.

The vast majority of Dan masters who don't have money, or half-baked alchemy apprentices, will build bellows in their own homes and set up furnaces for alchemy.

This is also the cheapest way to do alchemy.

The disadvantage is that the fire temperature is too low, and it can only be burned to the bottom of the Dan furnace. It can easily lead to uneven heating, which greatly reduces the success rate of alchemy.

Due to the cheapness, there are still many people who use it.

A better charcoal fire is coal, also known as graphite.

Its temperature can reach more than 1,000 degrees, which is comparable to earth fire.

It's a pity that graphite is difficult to dig up, and generally after the discovery of graphite mines, the local forces will immediately control it in their own hands.

This has also led to the price of graphite remaining high.

It's much easier to use than charcoal, not only does it have very good staying power, but it also has a high temperature.

The stability is a bit worse, but it's still acceptable.

In addition to charcoal and charcoal, there is also a higher level called animal charcoal. It is said that only some special birds and animals can take their inner pills or animal bones to make animal charcoal.

When it burns, it can release a blue flame at a frighteningly high temperature.

And it can be burned around the furnace wall like an ordinary flame, evenly covering most of the Dan furnace. Its stability, as well as its staying power, is very good.

It's a pity that the price of animal charcoal is ridiculously expensive. And it's extremely rare.

Even Chu Feng, the Immortal Danzun, could not use beast charcoal wantonly when he was the most beautiful in his previous life.

Many high-level Dan masters like to spend a lot of money to buy one or two pieces of beast charcoal treasures. It will only be used when refining some particularly valuable medicinal materials, or refining particularly important pills.

Just like many sword cultivators, they spend a lot of money to buy pills, and they are only willing to use them when they encounter bottlenecks or impact levels.

......

High-grade alchemy room, one hundred taels of silver a day. Chu Feng directly handed over a thousand taels of silver. Refund more and make up less.

Under the admiring gaze of Senior Brother Gatekeeper and He Ruoshui and others, Chu Feng strode into the alchemy field. Unlike the dormitories where they lived, the high-level alchemy room was built at the bottom of the valley. Because the lower the terrain, the purer and warmer the fire.

Chu Feng did not immediately enter the alchemy room, but walked towards the trading area in the alchemy hall.

There are sectarian medicine shops here, and as long as you have money, you can buy basically any kind of medicinal herbs. If you don't have money, you can also exchange merit for merit.

In addition, you can also recycle the refined elixir to the sect.

It's just that the price is lower than the market price, so after refining the pill, many people will choose to sell it to other disciples of the sect. In this way, you can earn a little more.

Even though it was morning, there were still many people setting up stalls to sell the pills they had refined.

Chu Feng only glanced at it slightly, and then entered the sect's pharmacy.

Unlike the for-profit pharmacies outside, the guys here are all disciples or deacons of the sect. All of them are cold and not enthusiastic.

Even if Chu Feng, a customer, entered the door, no one greeted him.

Chu Feng walked to the counter and carefully examined the medicinal herbs placed inside. Good guy, I really don't know if I don't see it, and I'm shocked when I see it.

There were so many rare medicinal materials on the counter that Chu Feng was dazzled.

Millennial medicinal herbs abound. There are also a lot of 10,000 years.

It is worthy of being the overlord sect of the Northern Regions, and with the countless masters under it, the various resources obtained are also very considerable.

"10,000-year-old red sun grass, the price is 30,000 taels of silver!"

"Ten thousand years of Da Luo Sword Grass, the price is 50,000 taels of silver!"

......

Chu Feng's eyes couldn't help but light up slightly, and his gaze was fixed on the four Ten Thousand Year Great Luo Sword Grass in the counter.

Take out just one of them, and it's enough to make a splash outside. There are several of them here.

The price is a little more expensive than the outside, which is understandable.

Because the sect is not stupid, in order to ensure that every medicinal herb is really used on the disciples of the sect. Naturally, it is necessary to prevent some people from deliberately buying medicinal materials from the sect at a low price and then selling them to people outside the sect.

Earn the difference from it.

The last time Chu Feng was at the auction, at a price of 45,000 taels of silver, he bought a 10,000-year-old Daluo Sword Grass.

The price of the sect is 5,000 taels more expensive, which is acceptable.

If you don't buy it with silver, you can also exchange it for meritorious deeds. The number of merit points marked above is 5,000 points.

It seems that a little merit is equivalent to ten taels of silver.

"I only have more than 30,000 taels of silver on me, and I can't afford it. I can only find a way to redeem the merits. I don't know how much merit I will be rewarded for rescuing Senior Brother Pu Fazheng last time?"

Chu Feng walked around the pharmacy, bought some auxiliary medicines for refining the Heaven-Defying Usurpation Pill, and spent four thousand five hundred taels of silver to buy two cod liver grasses that were more than a thousand years old.

It is a peculiarly shaped herb that looks like the liver of a fish.

Elongated, dark red. There are also some scales at the root.

Although the pharmacy is marked with a thousand-year-old portion, it is actually more than that. Ordinary pharmacists, it is difficult to identify its specific year. Chu Feng selected two plants from the large handful of cod liver grass.

All of them are more than 3,000 years old.

This is also equivalent to picking up the leak, because he has this eyesight.

Cod liver grass was not bought for personal use, but for Han Xiaoying to refine a healing pill.

She is Chu Feng's fiancée, and she has a deep affection for Chu Feng, so Chu Feng naturally wants to take good care of her.

After making preparations, Chu Feng entered an empty high-grade alchemy room.

I saw that the alchemy room was very tidy and tidy, and there were a variety of auxiliary medicines. In addition, there are soft beds that can be used to sleep. The Dan furnace is also made of nine-fire red copper. As for the furnace fire, it is needless to say, it is more than ten times purer than ordinary earth fire.

The flame is stable, the color is very pure, and it is very comfortable to look at.

The soft bed was basically an ornament, and it was estimated that no one would spend a hundred taels of silver a day to sleep in it. Unless you really can't spend all the money, that's pretty much it.

......

Three days passed in the blink of an eye, and when he first started alchemy, Chu Feng did not use his own fire.

Because the earth fire in the alchemy room was already able to meet his alchemy needs.

When refining the Heaven-Defying Pulse Pill, because the Taiyin Golden Lotus was too precious, no mistakes were allowed. Therefore, Chu Feng used his Jiuyang Alien Fire to perform alchemy.

As soon as his Jiuyang Alien Fire came out, all the surrounding alchemy rooms were affected.

The flames of the other Dan rooms all 'worshipped' to Chu Feng here.

It just so happened that there were two sect elders who were also refining here. One is Han Xiaoying's master, Elder Zhuang. The other person is Elder Shoumei.

They were shocked when they noticed something unusual in the fire.