The pine flower bud is made from the pine flower stone produced in the Changbai Mountain area of ​​Jilin. The use of loose stone stone began in the late Ming Dynasty and was admired in the Qing Dynasty. Songhua 砚 is warm and jealous, green and flawless, firm and thin, color is tender and pure, slippery and irresistible to ink, 涩 涩 , , , , , , , , , , 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松 松Emperor Kangxi appreciates Songhuayu, and seals it as “Yuyu”. It has been exclusively used by the court, and praised Songhuayu: “Shougu and quality, green and clear, and ink-free, so its treasure.

Technical requirements for quality of Songhua (Songhua Dendrobium) (1) Mining and processing. 1. Mining: (1) Hold the mining license of the relevant state department. (2) It is forbidden to use destructive mining methods such as blasting during mining to reasonably protect resources. (3) When excavating, use original tools such as hoes, shovel, etc., and use water drills, wooden wedges and excavation equipment during large mining. 2. Processing: The production process of Songhua (Songhua Dendrobium): material selection → design → processing. (1) Engraved by hand, carved. Designed according to the shape and color of the dip, and hand-engraved. (2) It is mainly made by hand and engraved by auxiliary engraving machine. The whole of the rafter is simply treated with a mechanical device such as a grinder, and then the pattern and figure of the hand-carved table are polished and polished. (3) Copying the Imperial Palace. The texture, color, brushwork and pattern of the imitation of the Imperial Palace are carved. (2) Quality characteristics. 1. Sensory features: Small particle size, dense texture, delicate texture, cool touch, slightly slippery feel. The color system is rich, the color is numerous, and the green color is mainly divided into seven green levels of emerald green, apple green, yellow yellow green, spinach green, green gray green, light gray green and dark gray green. 2. Physical and chemical indicators: (1) Mohs hardness: 4.0 to 4.5. (2) Density: 2.64 to 2.74 g/cm3. (3) Water absorption rate: 0.09% to 0.98%. (4) Compressive strength: 78.13 to 121.20 MPa. 3. Safety and other quality technical requirements: Product safety and other quality technical requirements must comply with relevant national regulations.

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Producers within the scope of production of Songhuayu (Songhua Dendrobium) may submit an application to the Jilin Provincial Bureau of Quality and Technical Supervision for the use of the “Special Mark for Geographical Indication Products”, which shall be reviewed by the Jilin Provincial Bureau of Quality and Technical Supervision and reported to the AQSIQ for approval. Announced. The statutory testing agency of Songhuayu (Songhua Dendrobium) is designated by the Jilin Provincial Bureau of Quality and Technical Supervision.