As a result, Haasgat is somewhat unusual in maintaining both the original roof and parietal contours, as well as remnant fossiliferous bands of calcified sediments throughout the ~100m long tunnel that comprises the modern cave.

[4][1] The extensive ex situ calificied sediment miner's dumps at Haasgat were sampled by Andre Keyser in the late 1980s, yielding a fossil assemblage that was partially described in a series of publications.

[1] Simultaneously, Keyser and Martini also suggested that the elevation of the system (near 1500m) and erosional deroofing prior to mining might indicate that the fossil deposits at Haasgat might have formed as early as the terminal Pliocene.

An evaluation of the extinct baboon (Papio angusticeps) sample, a species currently only known across African Pleistocene deposits in the Kromdraai A assemblage, were taken to suggest that the Haasgat fossils were roughly contemporaneous (~1.9-1.8 million years ago).

[5][8][9] In contrast, a description of the non-primate faunas from the ex situ dumpsite emphasised the largely modern ungulate sample and suggested a more recent depositional age of maximally 1.5 – 0.5 million years ago.