Cuoru Cailang (1926-2004) was a renowned Tibetan medicine expert, expert in ancient Tibetan literature, and a scholar of astronomy, calendar calculation, declaration, and Buddhism. Born in August 1926 in Dege, Sichuan. At the age of 7, he was recognized as the reincarnated living Buddha of Cuoru Temple. 1933-1959 Studied at Cuoru Temple in Jiangda County, Xizang, Gatu Temple in Sichuan and Lhasa. From 1960 to 1981, he practiced medicine in Xizang Bomi Farm and founded Bomi Tibetan Hospital. In October 1994, he served as the president, professor, master and doctoral supervisor of Xizang Tibetan Medical College. He wrote and compiled more than 180 treatises (books) focusing on Tibetan medicine and pharmacy, successfully developed "Tibetan medicine mercury processing and refining method", which promoted this ancient Tibetan medicine stunt, and guided the development of new anti hepatitis B drugs "206" and "209" to be included in the national torch plan. He used to be a member of the Standing Committee of the 8th CPPCC National Committee, a member of the 9th CPPCC National Committee, the Deputy Director General of the Chinese Tibetan Studies Center, the Executive Director of the Chinese Buddhist Association, the Vice President of the Xizang Astronomical Calendar Association, the Vice President of the Xizang Buddhist Association, and the Executive First Vice President of the Chinese Ethnic Medicine Association. President of the Xizang Tibetan Medical College (now Xizang Tibetan Medical University), the first chairman of the Zannuo Pharmaceutical Expert Advisory Committee, etc.

The ancient proverb 'True gold fears no fire' has a deeper meaning in the context of Tibetan medicine. The key to using metals such as gold and mercury in medicine lies in detoxification, and this is where the mystery and magic of traditional Tibetan medicine processing methods lie. From poison to medicine, transforming poison into medicine, this is the amazing mystery. In Tibetan medicine, there is a medicine that takes the wisdom of "transforming poison into medicine" to the extreme - it is called "Zotai".

Zotai, also known as "Renqing Ouqu Zuozhu Qinmu" or "Ganlu Jing Wang" in Tibetan, is a special potion made by refining "Eight Irons" and "Eight Treasures" with mercury. The so-called eight irons refer to metals such as gold, silver, copper, iron, lead, etc; The so-called Eight Treasures refer to minerals such as coral, agate, cat's eye stone, turquoise, etc. It is a preparation with unique therapeutic effects obtained by famous Tibetan doctors through special processing of highly toxic mercury throughout history. It is the mother of Tibetan medicine and is regarded as the most precious treasure among Tibetan medicines by the people of Xueyu, known as the "king of all medicines". Zotai is the main raw material for producing precious Tibetan medicines such as "Renqing Changjue" and "Shizhu Darcy", and is also used as a preparation to enhance the efficacy of ordinary drugs. Any medicine that contains ingredients from Zotai is labeled with the word "Renqing" in its name, forming the most precious "Renqing" series in Tibetan medicine. Without Zotai, many precious varieties of Tibetan medicine cannot be produced, so the "Mercury Purification Zotai Method" is a key technique for inheriting and developing Tibetan medicine production.

The mercury refining method is a recognized high difficulty technique in traditional Tibetan medicine production. It needs to extract Zotai from the highly toxic mercury to make the "starter" for many precious Tibetan medicines. The inheritance of this skill runs through the thousand year history of the development of Tibetan medicine. In the 8th century AD, the founder of Tibetan medicine and the ancient Tibetan medical saint Yuto Yundan Gongbu wrote the "Four Medical Classics", which already recorded the secret of refining Zotai. This is the earliest record of Zotai in Tibetan medical history books. At the end of the 13th century AD, the great sage Wu Jianba Renqinbei successfully carried out the entire practical operation of mercury processing, including cold and hot treatment and detoxification, and compiled works such as "Treatise on Mercury Production". Afterwards, he personally taught the technique to the third Karmapa Rangjung Dorje (1284-1339), and for the first time applied this technique to make the famous Karmapa black pill.

However, this skill that has been passed down for thousands of years suffered an almost fatal fracture in the mid-20th century. Due to various complex reasons, this skill disappeared without a trace. At that time, most of the people who had access to such secrets had already passed away, and Zotai had only become a legend in the entire Tibetan region, lost for more than fifty years. Without Zotai, many precious Tibetan medicines cannot be made; Without Zotai, the most brilliant "Renqing" series in Tibetan medicine would become a water without a source. This is the most critical moment in the history of Tibetan medicine development.

It was during this crisis that Tibetan medicine master Cuoru Cailang appeared. Cuoru Cailang was born on the banks of the Jinsha River in 1926. He studied Tibetan medicine theory from a young age and followed many famous teachers, eventually becoming a renowned physician of his generation. As early as his youth, he learned this skill at the Gatu Temple, and his special purification technique has long been engraved in his heart, unforgettable for a lifetime.

The problem faced by Cuoru Cailang was that although the theoretical configuration of "Zotai" was feasible, no one had personally made "Zotai" at that time. In 1978, he went to Dege Printing Institute in Sichuan to carefully review the classic records of the "mercury washing and refining method", and collected necessary smelting vessels and materials for processing and disinfection from various places. In extremely difficult and rudimentary conditions, he overcame various difficulties, went through more than a hundred complex processes, and worked tirelessly for 45 days day and night. Through the "Mercury Refining Zotai Method", he successfully processed the precious Tibetan medicine Zotai that had been lost for nearly 60 years. This great achievement successfully established the unshakable historical position of Master Cuoru Cailang in the development history of Tibetan medicine.

As one of the first batch of intangible cultural heritages in the country, the "Mercury Refining Zotai Method" is a top-level technique for Tibetan medicine processing. Its process is complex and intricate. In the Zotai Exhibition Hall of the Cangnuo Tibetan Medicine Culture Museum in Hebei Province, four sets of lifelike character portraits vividly reproduce this thousand year old skill. The entire process takes more than 30 people and 45 days of manual labor day and night to complete, while traditional methods require about 420 hours. Any slight mishandling of the production process will fail to achieve the goal of detoxification, or insufficient force and heat will result in failure. In order to make this unique skill no longer lost, Chou Ru Cailang also wrote the Essence of the "Sitting on the Stage" Method of Mercury Refining, and patiently trained dozens of apprentices, the most representative of whom is Professor Sorang Qimei, his nephew who followed Master Chou Ru Cailang when he was young (the representative successor of the national intangible cultural heritage project Tibetan Medicine (Lhasa Northern Tibetan Medicine Mercury Refining Method), and the director of Xizang Zannuo Pharmaceutical).

The Hebei Zangnuo Tibetan Medicine Culture Museum is the only comprehensive provincial-level museum in mainland China with Tibetan medicine culture as its theme. It was officially unveiled on August 8, 2024. The venue covers an area of 2000 square meters and houses a collection of 304 items. It features 16 exhibition halls, including the integration of Han and Tibetan ethnic groups, the history of Tibetan medicine development, Tibetan medicinal specimens, Tibetan medicine processing techniques, and a grand view of the modern Tibetan medicine industry. One of the most distinctive core exhibition areas of the museum is the "National First Batch of Intangible Cultural Heritage - Mercury Purification Method" exhibition hall. Professor Wang Zhisen, the direct disciple of Master Cuoru Cailang and the chairman of Cangnuo Pharmaceutical, is the inheritor of this tradition in contemporary times. He deeply reminisced about his mentor's lifelong promotion of the noble realm of Tibetan medicine, restored the legendary journey of secret techniques such as Zotai, and made the museum an important platform for showcasing and promoting Tibetan medicine culture in mainland China.