Australia: The Land Where Time Began

A biography of the Australian continent 

Sydney-Hawkesbury Rock Engravings - A Mangrove Mountain Engraving Tool

On the east coast of Australia Aboriginal rock engravings in the Sydney-Hawkesbury region were commented on by the first British colonists, though there is no description of the method used to make them. A basalt stone tool that was found at an engraving site in the Mangrove Mountain area of the Central Coast of New South Wales and the use-wear analysis of this stone tool supports the supposition of the finder that it was a rock engraving tool. It was indicated by the analysis that the tool was used for both pecking and abrading rock that was coarse grained – actions that had been used to make the Sydney-Hawkesbury rock engravings by the “conjoined-puncturing” technique. In order to test the usefulness and efficiency of basalt tools for making rock engravings and to produce wear traces for comparative functional analysis an experimental study was undertaken. It was suggested by the use-wear analysis that this tool was also used for preparing skins.

There are more than 2,000 Aboriginal rock engravings in the landscape of the Sydney-Hawkesbury sandstone (Stanbury & Clegg, 1990: 2), which were made in a distinctive style of Simple Figurative rock art (Franklin, 19984: 89; Maynard, 1976; McDonald, 2008). The number of petroglyphs (engraved figures) at each site ranges from a single figure up to 174 (McDonald, 2008: 51).

In 1788, officers of the British First Fleet who had arrived in Port Jackson (Sydney Harbour) commented on the existence of the rock engravings in their reports and journals (e.g. Phillip, 1982: 135 [1788]; Tench, 1979: 47 [1789]: 79]). It appears, however, that they didn’t see them being made, and no descriptions are known of the tools that were used to make the engraved outlines. The earliest recorded observations of the engravings being made was not until the late 1800s, and on that occasion a metal axe was used (Mathews, 1897). It had been suggested that the original engraving tools included sharpened pieces of ironstone or other stones/pebbles, bone or wood, sharp-pointed whelk shells, as well as a “stone tomahawk” (e.g. Clegg, 1979: 42-3; Mathews, 1895a [1894]: 146; Mathews, 1895b: 149-50; Stanbury & Clegg, 1990: 1, 119-20).

The technique that had been used to make the engravings is referred to as “conjoined-puncturing” (e.g. Mathews, 1895a [1894]: 146; Mathews, 1895b: 149-50; McCarthy, 1959: 205). In many of the engraved lines the pits or “scalloped” edges suggest a 2-stsage process: first, a series of pits were made and these could have a diameter of up to 30 mm and up to 10 mm deep. It is common for the pits to overlap to form a continuous groove, though some pits are up to 30 mm apart. Subsequently, the pits and intervening spaces were abraded to produce a continuous groove of the depth and width that were required, sometimes up to 60 mm wide and 60 mm deep. The U-shaped groves forming most figures at the present are often less than 10 mm deep and 20 mm wide (e.g. Mathews, 1895a, [1894]: 146-7; Mathews, 1895b: 149-50; McCarthy, 1938: 401; Stanbury & Clegg, 1990: 1, 119-20).

Wood, stone, shell and bone were used on both wet and dry Hawkesbury sandstone in this experiment (Clegg, 1979: 42-3) using techniques termed “hacking” (handheld or hammered) and “drilling” (rotary) by Clegg. It was found by Clegg that to form the combination of hacking and drilling was better for forming the pits than hacking alone. A small water-lubricated stone was used to smooth/abrade. Clegg did not provide morphological or metrical details, however, of the tools that were used to make the pits and grooves or of the pits and grooves that he made.

A tool made from basalt was found on a sandstone platform “beside an unfinished Aboriginal engraving of an emu’s head” (Australian Museum Archives 504/38) in the area of Mangrove Mountain, New South Wales Central Coast in the 1930s. The finder, Roy Mackenzie, stated, based on its association with the engraving of the emu’s head, that “it is thought to have been used for engraving” (AM registry entry for E04612 and Ascension Schedule 352; McCarthy, 1938: 401; McCarthy, 1976: 63-5, Fig. 48.2; McCarthy et al., 1946: 66, fig. 308; see also Attenbrow, 2010: 147). The stone tool that is referred to below as the Mangrove Mountain [MM] tool is now in the Australian Museum Archaeology Collection. It is indicated by PXRF analysis that it is a piece of basalt from Peats Ridge/Popran Creek (Kulnura) in the local area. It is of a quadrangular shape with a length of 99 mm and a thickness of 44 mm (maximum dimensions) (McCarthy et al., 1946: 66, fig. 308). It has an edge that is battered, abraded and rounded, with obvious striations and black residues embedded into used surfaces (Tables 1 and 2). It has no ground bevelled edge. The black residues are of variable thickness, sufficiently thin in parts to enable striations in the surface of the rock to be seen beneath it, but thickness elsewhere is enough to see striations embedded within it.

Discussion and conclusions

On the Mangrove Mountain tool there is use-wear evidence of its use for processing animal skins that parallels other evidence of processing and working animal skins in the New South Wales Central Coast hinterland; e.g., on artefacts with ground edges called Bulga knives (Kononenko lab Notes 2016) and on backed artefacts (Attenbrow et al., 2009; Robertson & Attenbrow, 2008; Robertson et al., 2009). One of the mission people from Lake Macquarie was recorded in 1826 by Rev. Lancelot Threlkeld (1974: 206) to have gone “to the mountains with upwards of 60 spears to trade for possum skin cord made of the fur”, and to participate in a ceremony. It is not indicated by Threlkeld if “the mountains” included Mangrove Mountain, though his statement indicates that the workings of animal skins/fur took place in hinterland regions of the New South Wales Central Coast. The use of the tool for rock engravings is overlain by use-wear indications of skin working. The question is was processing skins part of the activities that were associated with the making of rock engravings at the site of the Mangrove Mountain tool find, or as part of the trading that occurred in the context of procuring basalt for the manufacture of hatchets from Peats Ridge, or whether Mangrove Mountain was a gathering place of the people for ceremonies (Attenbrow et al., 2017). It is indicated that the final stage of the tool’s use-life was for processing animal skins so the tool could have been used in the processing of animal skin elsewhere prior to being brought to the site of the engraving on which it was found.

This is the first tool that has been identified with a degree of certainty as being used in the making of the Sydney-Hawkesbury rock engravings. The finder’s suggestion that this tool was used for the making of rock engravings is supported by the use-wear analysis, though not necessarily at the site at which it was found, in spite of the presence of an unfinished engraving at that site. The tool had been used for the making of rock engravings, pits and abrading coarse-grained rock to form grooves – actions that were used to make the Sydney-Hawkesbury rock engravings in a technique known as conjoined-puncturing.

Sources & Further reading

1. Attenbrow, V. A. L. and N. Kononenko (2017). "Creating Sydney-Hawkesbury rock engravings: A Mangrove Mountain engraving tool." Archaeology in Oceania 52(3): 161-170.