Twenty-four archaeological sites, with remains of the same culture as Hac Sa, have been located in the coastal areas and islands of the Zhujiang estuary (Yang Shiting 1998, 48); most dates fall between 3000 and 4000 BC. In Hong Kong and Macau, jade rings and ornaments occur in clusters, and the stone materials are said to be regionally distinctive (Yang Shiting 1998, 51). It has been suggested (ibid) that proof that these items were locally made lies partly in the fact that many of these sites contained stone source material. The source materials reported from other similar sites include: colourless transparent crystal, milky white streaky quartz, chalcedony, marble containing mica (very unusual), sedimentary rock, agate, kaolinite, tremolite and volcanic rock (Yang Shiting 1998, 51-2).
Comment: This wide range of lithic source material could be examined petrologically to help differentiate between sites and to establish possible dispersal patterns.
Although the placing of jade artefacts in ceremonial tombs was fairly typical in the central China plains, dating from the Yin period of the Shang dynasty, the placing of jade grave goods declined rapidly during the Xizhou (Western Zhou) dynasty around 1100-700 years b.c.
Comment: How does the chronology for the use of jade in Chinese prehistory compare with the period of production at the Hac Sa and other workshops in the Zhujiang estuary?
It is for the manufacture of ornamental stone rings – the Yu Shi workshops, not stone tools – that the Hac Sa sites appear to be important. Ornamental rings of similar style and age also occur widely across the Zhujiang estuary, and further afield, e.g. Lake Baikal in Siberia, Angola, Java, Japan, the Lo Jia Jiao in Zhejiang Province, Hong Kong, Taiwan and Vietnam – they are not unique to Coloane. The great majority of these Yu Shi ornamental workshops are associated with either sand dunes or river sand deposits. Excavation evidence from the Hac Sa Yu Shi workshop suggested that quartz pebbles were being utilised for ring-making.
Comment: the mode of crystallisation and the morphological characteristics of the material suggest that quartz gathered from the hillsides and possibly from outcrops may have also been utilised. The mapping and sampling of the quartz veins, especially those that display similar characteristics to the excavated archaeological finds, may prove worthwhile.
Yang Shiting (1998, 52) asks some interesting questions, for example: why have so many quartz and rock crystal ornaments and remains been found in Hong Kong, Macau and around the Zhujiang estuary? Was it because of easy access to the raw material? Were the finished ornaments made at the Yu Shi workshops then transported to the interior of Guangdong?
Comment: evidence from a field-based programme of geochemical analysis using PXRF for example, might help to answer these important questions.
Traditionally, the term Jade has been used to describe almost any 'beautiful stone'. For example, rock crystal 'shuiyu' was called 'water jade' in the Jin dynasty (1115-1234 b.c.) (Yang Shiting 1998, 39), and referred to all crystal. Rock crystal is usually cryptocrystalline silica of even texture, or a pure and large single crystal. Unfortunately, the term 'jade' is currently used in Chinese archaeology, and more widely, in two ways – traditional (nephrite, jadeite, eclogite, amphibolite, serpentinite, jasper, rock crystal and chalcedony); and scientific (nephrite and jadeite).
Comment: It would be helpful if, on future occasions, contributors to the literature clarified whether they were using the term 'jade' in a traditional or scientific sense, preferably the latter.
Both of the Hac Sa sites face the sea and are sheltered from the prevailing winds by hills; they had running water and a lagoon to provide fresh drinking water. Stone carvings occur elsewhere in the Zhujiang estuary, e.g. Lantau Island HK, possibly associated with stone manufacturing sites, and which may reflect their style of spirituality (Yang Shiting 1998, 54).
Comment: a field survey of the landscape features adjacent to the Coloane archaeological sites might reveal the possible existence of rock art.
It is supposed that the sea level rose to its present level by 6000 bp. Interglacial cycles have caused major fluctuations in world sea levels, from a glacial maximum around 75,000 years ago when the sea level fell by about 77 metres below the present level. The last glaciation started around 25,000 years ago, and the present sea level fell by around 125 metres between 18,000 and 17,000 bp. Therefore, the shallow coastal waters around Hac Sa today may have been rivers and river terraces during the early prehistoric period in the Zhujiang estuary.
Comment: what are the implications of changes in sea level for the early history of the Coloane archaeological sites, and more widely across the Zhujiang estuary? What range of rock types is represented in the glacial, fluvial and beach deposits available at the sites? Does this availability match the rocks in the stone tool record?
Stepped and shouldered stone implements occur throughout China. The shouldered tool type occurs extensively along the west coast of the Pacific. It has been classified into three groups: axe, adze and shovel. Each was thought to have originated independently. The shouldered adze is thought to have first developed in the Zhujiang estuary region, with typological links with the Philippines, the Pacific Islands and SE Asia. A comprehensive catalogue has been published for the stone adzes of Hong Kong (Rogers and Ward, undated), which provides a suitable typology for classifying the 52 types of adze found in Hong Kong.
Comment: What can we learn about the evolution of stone tool-types and their stylistic variants using lithic evidence from excavations or stray finds from Macau, Coloane and Taipa, and more widely across other archaeological sites in the Zhujiang estuary?
Comment: Greater consistency in the reporting of stone adze tools from Macau and across the Zhujiang estuary would be achieved by using the typology developed for the recording and reporting of adzes in Hong Kong.
Comment: A macroscopic identification has been provided for only some of the stone adzes from Hong Kong. It is clear from illustrations provided in the catalogue (Rogers and Ward, undated) that several adzes appear sufficiently similar to have probably originated from the same location. From a close inspection, adze No. 3021-95HST6 from the Hac Sa excavation closely resembles some of the adzes from sites in Hong Kong. A programme of microscopic identifications, supported by geochemical analysis, might point to procurement sources, manufacturing sites and patterns of distribution.
In conclusion, this article has attempted to address concerns in the literature regarding the serious need for more archaeological research into the prehistory of Macau. The potential for a systematic programme of implement petrological research in Macau, and more widely across the Zhujiang estuary and adjacent areas, has been demonstrated. Such a survey might be expected to contribute very significantly to our current levels of knowledge and understanding regarding the procurement, manufacture, use, dispersal and deposition of prehistoric stone tools in south-eastern China.
© Internet Archaeology/Author(s) URL: http://intarch.ac.uk/journal/issue26/7/5.html
Last updated: Wed Jun 10 2009