Archaeological Discoveries and Studies on Raised Beaches and Saltwork Stoves in Hong Kong
From：Chinese Archaeology Writer： Dr. Li Long Lam Date：2008-08-22
Between the Southern Dynasties (420-589) and the Tang (618 – 907) Dynasty, the continuation of high temperature had caused a relatively higher sea level of one metre above current Principle Datum. This resulted in the forming of secondary raised beaches along the prehistoric raised beaches in the Pearl River coasts. Saltwork stoves remains along almost every secondary raised beach were a relatively untouched topic in Archaeological excavations and research. This caused a lack of understanding of saltwork industry as a main revenue for the imperial courts of ancient dynasties. There are many historical documents regarding Yan Guan (saltwork officer) and salt tax, which has displayed how the imperial courts highly priced the prosperous saltwork industry and its management in the Peal River Delta.
According to archaeological excavations and site conditions, the 56 sites of stove sites between the Southern dynasties and Tang dynasty can be classified into five categories. Category A are those surveyed or excavated sites in which the basic cultural context has been clarified. Category B are those sites where the top of stoves have been exposed, but without solid quantitative data. Category others are those with lots of stove furniture being recovered, but with no information regarding the exact location of the once-existed stoves. All stoves were semi-buried with their openings and ventilation channel on the ground surface, and thus causing temperature the stoves to be about 600˚C. These stoves were located with proximity to the sea on the secondary raised beaches. Ancient method for salt production was to boil down the brine. Various documents including The illustrations of Aopo and The Heavenly Creations have provided detailed descriptions of saltwork production sequences and equipments. The structure of stoves found in Hong Kong is similar to those being described in those ancient records. Since the 1930s, stoves discovered in Hong Kong have long been interpreted as lime or ceramic kilns Based on historical records, the particular natural environment and resources, as well as the climatic changes and the rise of sea level, these stoves contained characteristics that was totally different from lime and ceramic kilns in terms of quantity, structure and stove temperature. It could only be regarded as saltwork stove. This indicated that the population between Southern dynasties and the Tang dynasty did not only fish from the sea, but also utilised the brine for saltwork industry.
The study of saltworks prior to Tang dynasty only commenced recently, with most topics require in depth research. Nonetheless, the re-understanding of these saltwork stoves would prominently contribute towards saltwork industry and the environmental archaeology during the Han-Tang period, in not only South China, but also in the geographic region of China.