Expedient shell tool use among Oceanic peoples is widely known in ethnographic context but oftentimes almost impossible to identify in the archaeological record. This paper examines Anadara antiquata bivalve scrapers, a potential artefact type in the Kingdom of Tonga that is defined by a consistently formed ventral margin. To assess the veracity of tool identification and to ensure that the edge has not been created through natural breakage, a series of experimental studies was undertaken. These illustrate that the functional edge can be formed only through intentional preparation using an inside-out flaking technique on the ventral lip. A low-powered starch test on archaeological specimens further illustrates the presence of starch on the prepared working plane. Finally, an analysis of archaeological specimens from five Tongan sites seeks additional insight on morphological variation within the tool type.

中文翻译：

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汤加考古记录中的Anadara antiquata双壳类刮刀问题

海洋民族使用贝壳工具的便利在人种学背景下广为人知，但在考古记录中通常几乎不可能识别。本文研究了 Anadara antiquata 双壳类刮刀，这是汤加王国的一种潜在人工制品类型，由一致形成的腹侧边缘定义。为了评估刀具识别的准确性并确保边缘不是通过自然断裂产生的，进行了一系列实验研究。这些说明功能边缘只能通过在腹唇上使用由内向外剥落技术的有意制备来形成。考古标本的低功率淀粉测试进一步说明了在准备好的工作平面上存在淀粉。最后，