Black salt, also known as saindhav, kala namak, or sanchal, is harvested on land, around volcanoes, though some say it was formed by ancient seas that dried up. It is harvested in Central India though I have found a Pakistani company that sells this salt. It starts out black but turns pink when it is crushed. It is the essential sulfurous ingredient in Chat Masala, along with other ingredients (ajwain, fennel, asafoetida) prized for their ayuredic properties, particulary as digestives.
An absolutely fascinating ingredient. I bought it months ago, after finding it in a recipe I can no longer find, but thinking it just might come in handy. As I was looking for bean salads, I discovered the world of chat and within that world a mini-universe of chat masala.
Found some interesting historical information in a translation of "The Hou Hanshu, the official history of the Later (or ‘Eastern’) Han Dynasty (25-221 CE), [which] was compiled by Fan Ye, who died in 445 CE." This document notes that black salt was found in the kingdom of Tianzhu (Northwestern) India:
heiyan 黑鹽 [hei-yen] = literally: “black salt.” “Black salt,” or vida, is still used in Indian cooking today. It is first mentioned in the two great Indian epics, the Ramayana and Mahabharata where it was prohibited from being used in ceremonies for the ancestors. Charaka, who is said to have been the personal physician of the Kushan Emperor Kanishka, and is famous as the “father of Indian medicine,” included it in his list of five types of salt – Achaya (1994), pp. 37, 86.
Black salt is produced by fusing rock salt with Indian Gooseberry, the astringent fruit of an Indian tree Phyllanthus emblica, which is also used for tanning and making inks. It is employed in Indian medicine as a tonic, aperient or laxative. Monier-Williams (1899), p. 962.
Also of interest is the information kindly sent to me as a personal communication by John Moffett, Librarian, East Asian History of Science Library, Needham Research Institute, on 7th September 1999:
“I have not been able to find hei yan in modern Chinese herbals, but here is what I have got. As usual, Laufer’s Sino-Iranica is the most informative (Chicago: Field Museum of Natural History, Publication 201, 1919), p. 511:
“The Pei hu lu distinguishes red, purple, black, blue, and yellow salts.... Black salt (hei yen) was a product of the country Ts’ao (Jaguda) north of the Ts’un lin [Sui shu, ch. 83 p.8]. It is likewise attributed to Southern India [Tang Shu, Cj. 221 A, p. 10b]. These coloured salts may have been impure salt of minerals of a different origin.”
The Han yu da ci dian, vol. 11 p. 1341 merely says it is a “salt used in medicine,” and quotes the Li Xiaobo zhuan in the Bei Shi, “... black salt treats abdominal distention and fullness of qi....” It does not look as if anyone has otherwise identified it as a specific mineral...”
And, finally, the inclusion of “black salt” as a tribute item:
“Black Salt” came as tribute in the joint mission of Turgäch, Chāch, Kish, Māimargh, and Kapiśa in 746 (along with “red salt”), and in 751 and 753 also came from Khwārizm, south of the Oxus .... The identity of this substance is not known.” Schafer (1963), p. 217.
In addition to its virtues as a tasty ingredient and digestive, it "is a common ingredient in jinx-removing spells. One common spell calls for sprinkling black salt on the property line separating you from an irritating neighbor." Here is a nice drink.
Jal Jeera — Indian cumin lemonade
3 cups of ice water
1 tablespoon ground cumin
1 teaspoon mint leave paste
2 tablespoon lemon juice
½ teaspoon kala namak
pinch of sugar
½ teaspoon cilantro (coriander) paste
½ teaspoon dry mango powder (amchur)
Mix well and served chilled with ice and garnished with mint leaves.
On black salt as an ingredient in Chat Masala, see earlier entry on the Chatpati Channa Chaat served at today's studio lunch.