Located in the Sundays River Valley, in the District of Cacadu District Municipality, Eastern Cape.

Aluin Krantz West is a Farm and the estimated terrain elevation Above Sea Level is; 199 metres. 28 km North-West of Alexandria. The Name means in  Dutch  'alum cliff', and refers to the occurrence of this mineral there, of Fibrous Alum. However, different substances were distinguished by the name of 'alumen', but they were all characterised by a certain degree of astringency, and were all employed in dyeing and medicine, the light-colored alumen being useful in brilliant dyes, the dark-colored only in dyeing black or very dark colors. One species was a liquid, which was apt to be adulterated; but when pure it had the property of blackening when added to pomegranate juice. This property seems to characterize a solution of iron sulfate in water; a solution of ordinary alum would possess no such properties. There is another kind of alum that the Greeks call 'schiston', which "splits into filaments of a whitish colour", it appears that this species was the salt that forms spontaneously on certain salty minerals, as alum slate and bituminous shale, and consists chiefly of sulfates of iron and aluminium. In some places the iron sulfate may have been lacking, so the salt would be white. 

Geolocation
26° 7' 12", -33° 19' 48"
References

New Dictionary of South African Names by Peter E Raper

https://www.mindat.org/feature-1023041.html
http://za.geoview.info/aluin_krantz_west,1023041