Science. 1975 Jan 10;187(4171):57-8. doi: 10.1126/science.187.4171.57.
Rare earth element abundances in soapstone from quarries and artifacts in eastern Virginia were determined by instrumental neutron activation analysis. By comparing these abundances it was possible to trace artifactual material to the outcrops which served as the source of this material during the first millennium B.C. Certain known sociopolitical boundaries in prehistoric Virginia were inferred to be older than previously assumed.
仪器中子活化分析测定了弗吉尼亚州东部采石场和文物中皂石的稀土元素丰度。通过比较这些丰度，可以追踪到人工制品的产地，这些产地是公元前一千年期间该材料的来源。推断出弗吉尼亚州史前时期的某些已知社会政治边界比以前假设的要古老。
