The history of the Rock Salt dates back to the Alexander era in the 326 B.C. However, in Pakistan, it is arguably amongst the best which can be found in the world as it directly extracted from the Khewra mines in Punjab. The salt was extracted by the horses of Alexander the great, who fought a battle with the Raja Pours on the River Jhelum which is 35 km away from the Khewra which eventually led to the discovery of Rock Salt. It is the largest and richest salt fields all over the world. The salt range starts over 186 miles (300 kilometres) along with the average height of 2200 ft. It mainly starts from the Baganwala near River Jhelum to River Indus. Surprisingly, the Khewra chasm is also acknowledged as “Museum of Geology” which was owned and operated by Janjua Rajas. After their invasion, the British Government took the control of these Salt Mines.
The purity of Rock Salt can be claimed at 99% with 1% of impurities which can be caused during the extraction process. Moreover, there are four different genres of rock salts which are pink solid crystals, white solid crystals, soft crystalline lumps, and soft lumps. Among these, the soft crystalline is found to be soft that one can effortlessly break them down with their bare hands.
Pakistan is an exceptional country for the production of salt due to the existence of different salt ranges. However, these salt ranges stretch from the Kalabagh to River Jhelum in the Punjab province. According to the geological surveys carried out by Pakistan Mineral Development Corporation (PMDC), it was revealed that 2.65 billion tons of salt are present in NWFP alone. In addition, the reserves at Bahadurkhel in Kohat were estimated to be at 10.54 billion tons.
In the historical background of the salt extraction, the salt was taken out from the mines of the salt which seems to the exposed to the people who were living in the vicinity. Dr Warth, a prominent Mining Engineer of the UK found a main tunnel at the ground level in the year 1872 for having a convenient and direct approach towards salt deposits. Moreover, the scientific mining system which was initially introduced by Dr Warth in the year 1872 is still in the trend. In the present situation, there are around 17 levels in the Khewra Mines. Under this system, there are only 50% of salt which is exhumed from the extraction, whereas, 50% of the working system is considered as the pillars for the support of mine.