（《唐本草》）
【释名】石盐（《唐本》）、圣石（《蜀本》）、水晶盐（《纲目》）。
时珍曰∶雷 《炮炙论》序云∶圣石开盲，明目而如云离日。则光明者，乃兼形色与功
而名也。
【集解】恭曰∶光明盐，生盐州五原，盐池下凿取之。大者如升，皆正方光彻。
颂曰∶今阶州出一种石盐，生山石中，不由煎炼，自然成盐，色甚明莹，彼人甚贵之，
云即光明盐也。
时珍曰∶石盐有山产、水产二种。山产者即崖盐也，一名生盐，生山崖之间，状如白
矾，出于阶、成、陵、凤、永、康诸处。水产者，生池底，状如水晶、石英，出西域诸处。
《吴录》云∶天竺有新淘水，味甘美，下有石盐，白如水晶。又波斯出自然白盐，如细石子。
金幼孜《北征录》云∶北虏有盐海子，出白盐，莹洁如水晶。又有盐池盐，色或青或白，军
士采食之。此皆水产者也。《梁四公子传》云∶高昌国烧羊山出盐，大者如斗，状白如玉。
月望收者，其纹理粗，明澈如水；非月望收者，其纹理密。金楼子云∶胡中白盐，产于崖，
映月光明洞澈如水晶。胡人以供国厨，名君王盐，亦名玉华盐。此则山产者也。皆自然之盐，
所谓天成者也。《益州记》云∶汶山有咸石，以水渍而煎之成盐。此亦石盐之类，而稍不同
者。
【气味】咸、甘，平，无毒。
【主治】头痛诸风，目赤痛，多眵泪（《唐本》）。
【发明】时珍曰∶光明盐得清明之气，盐之至精者也，故入头风眼目诸药尤良。其他功
同戎盐，而力差次之。
(From *Tang Bencao*)
[Names] Shiyan (Rock Salt, from *Tang Bencao*), Shengshi (Holy Stone, from *Shu Ben*), Shuijingyan (Crystal Salt, from *Bencao Gangmu*).
Li Shizhen said: Lei Xiao wrote in the preface of *Paozhi Lun*: "Shengshi can treat cataracts, brightening the eyes as if clouds disperse and the sun reappears." Therefore, the name "Guangming" (Bright/Luminous) refers to both its appearance and its efficacy.
[Collected Explanations] Su Gong said: Guangmingyan is produced in Wuyuan, Yanzhou, excavated from the bottom of salt pools. The large pieces are as big as a sheng (a unit of volume), all square, smooth, and transparent.
Su Song said: Currently, Jiezhou produces a type of rock salt that grows within mountain rocks, formed naturally without boiling or refining. Its color is very clear and crystalline; locals prize it highly, claiming it is indeed Guangmingyan.
Li Shizhen said: There are two types of rock salt: those produced in mountains and those produced in water. Mountain-produced ones are cliff salts, also known as raw salts, growing between cliffs, resembling white alum, found in places such as Jie, Cheng, Ling, Feng, Yongning, and Yongkang. Water-produced ones grow at the bottom of pools, resembling crystal or quartz, found in various regions of the Western Regions.
*Wu Lu* records: In Tianzhu (India), there is newly washed water with a sweet and pleasant taste; beneath it lies rock salt, white as crystal. Additionally, Persia produces natural white salt, resembling small pebbles. Jin Youxi’s *Beizheng Lu* records: The northern nomads have a "Salt Sea Lake" producing white salt, translucent and clean like crystal. There is also pool salt, which may be green or white, collected and eaten by soldiers. These are all water-produced. *Liang Si Gongzi Zhuan* records: Gaochang State's Sheep-Burning Mountain produces salt, large pieces being as big as a dou, white as jade. Salt harvested on the full moon has coarse texture and clarity like water; salt harvested otherwise has dense texture. *Jinlouzi* records: White salt in Hu lands is produced on cliffs, shining through like crystal when illuminated by the moon. The Hu people used it for state kitchens, naming it Junwangyan (King's Salt) or Yuhuatan (Jade Flower Salt). This is mountain-produced. All are natural salts, so-called "heaven-made." *Yizhou Ji* records: Wenshan has salty stones, which are soaked in water and boiled to make salt. This also belongs to the category of rock salt but differs slightly.
[Flavor and Toxicity] Salty and sweet, neutral in nature, non-toxic.
[Indications] Headache and various wind syndromes, red and painful eyes, excessive eye discharge and tearing (from *Tang Bencao*).
[Elucidation] Li Shizhen said: Guangmingyan obtains the essence of clarity and brightness; it is the most refined form of salt. Therefore, it is particularly effective in formulas treating head wind and eye disorders. Its other functions are similar to Rongyan (Rouge Salt), though its potency is somewhat inferior.