Dallol

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Potash is of economic value as fertilizer component. Consequently, the recognition of surface deposits of carnallite by the Black Mountains in 1906, by the Italian T. Pastori, was soon followed by first extraction attempts. The Italian Compagnia Mineraria Coloniale (CMC) installed mining infrastructure at Dallol. The main settlement appears to have been on Dallol mountain (presumably to avoid flooding during the rainy season). Transport was initially by camel all the way to the coast. However, from 1917-1918, CMC constructed a 60cm-gauge Decauville railway in Eritrea (Decauville = ready-made sections of small-gauge track which can be rapidly assembled) which served to transport the salt from Kulluli near the Ethiopian border to the small port of Mersa Fatma. From here the salts were shipped by dhows to the deep water port of Massawa, where they were then loaded onto larger ships for export. No railway was built on Ethiopian territory so the first 28km from Dallol were covered using lorries. During WW I, the allies obtained much of their potash from Dallol (Holmes, Geol. Mag. 6, p.340-343 (1919)). One source (Guida dell' Africa Orientale, Consociazone Turistica Italiana, Milano, 1938) indicates that in 1918, 20000 tonnes of potash analog were extracted and sold to Stassfurt Salt in germany. This seems rather unlikely since the germans were not short of potash at the time and were at war with the allies till near the end of that year.

The actual mining initially took place at the carnallite / sylvite deposit by the Black Mountain and involved, amongst other techniques, flooding of salt pans around a continuously flowing hot spring and harvesting of potash-rich salts therefrom after deliquescence removed most of the MgCl2 (Holwerda and Hutchinson, 1958). It is questionable if mining was restricted to the Black Mountain area. Apparently, local Afars tell of a deep mine that was present on Dallol Mountain in the vicinity of the mining village (Luigi Cantamessa, personal communication). No entrance to a deep mine is visible today. However, what appear to be the axles of mining cars from a narrow-gauge railway are found in Dallol village. On the other hand, the idea of deep-mining in an active geothermal area seems problematic.

The mine(s) appear to have been operational until 1929 when operations ceased due to increasing tensions between Italy and Ethiopia and due to easier availability of potash from the US, USSR and Germany. About 70000 tonnes of potash were recovered during the period up to 1929. Between 1925 and 1929, 25000 tonnes were extracted (Mohr, Geology 1961, p.239-240). The railway line was also closed in 1929 and it is reported that it was eventually dismantled and shipped to India by British troops during WW II (L.C., pers. comm.).
It is presently unclear what happened at Dallol in 1930s. It appears that the mine was not totally abandoned in the 1930s since it was sabotaged by Italian troops from the nearby military camp before British soldiers arrived in 1941 and the US Bureau of Mines Annual Report of 1940 included reference to mining of salts at Dallol in 1940. Plans to extend a railway all the way to Dallol had apparently been made (this may have indeed occurred (is currently being investigated), especially after Italy conquered Ethiopia in 1936 and formed Africa Orientale Italiana, which encompassed both Ethiopia and Eritrea). Although the mining infrastructure was sabotaged (this possibly accounting for the lack of a visible mine entrance today), the remains of many of the buildings still remain. This includes remnants of workers dwellings, the walls of which were constructed using blocks of salt.

The beautiful hot springs at Dallol are attracting increasing numbers of tourists, with many tour operators organizing tours into the Danakil Depression to see the Springs and Erta Ale volcano further south. Dallol can presently be reached by 4WD vehicle in 1 day from Mekele and 2 days from the main Addis-Djibouti road. However, 2007 and 2008 have seen repeated attacks on tourist convoys by what appear to be Afar Separatists from the Afar Revolutionary Democratic Unity Front (ARDUF). The establishment of improved infrastructure may increase security, yet even the current small stream of tourists is causing visible damage to the fine structures in the geothermal area.