Sourcing Midwestern Catlinites and Pipestones using a PIMA Spectrometer

在美国国家科学基金会的支持下，Sarah Wisseman博士和她的同事们使用了一台小型便携式红外矿物分析仪（PIMA）来定位用于制作管道和雕像的石材来源，这些管道和雕像可以追溯到中部林地（约1000年）。公元前50年至公元250年），后来在美国东部。该项目将考古学家和地质学家联合起来，以更好地定义中西部史前和历史社会使用的材料的性质，以及原材料来源，生产模式和成品文物贸易之间的关系。PIMA光谱仪是现代分析仪器的一个准确和精确的补充，其优点是易于操作，快速（每次阅读30秒），并且完全无损。 PIMA同样可用于野外或博物馆环境，并已成功用于确定矿物成分和无法破坏性取样的有价值文物的可能来源。 例如，PIMA读数被认为是来自密西西比的博物馆雕像，但没有出处的文件。令人惊讶的是，分析显示，与来自密苏里州东部采石场的燧石粘土很好地匹配，从该团队以前的工作中得知，这是大部分中密西西比州（约1000年）的来源。公元1000年至1400年）在东圣路易斯的卡霍基亚遗址或附近发现的“红色女神”雕像。在另一个例子中，PIMA的读数证实了在伊利诺斯州北方发现的霍普韦尔式（中部林地）管道的管道石的当地来源，否定了早期的理论，即所有这些管道都是在俄亥俄州制造的，然后被交易到西部。PIMA技术是X射线衍射（XRD）的补充，XRD是一种成熟的实验室技术，被团队用于检查和改进成分读数。研究小组正在使用这两种技术来建立一个特定于中西部的石材参考数据库。 当前项目的重点是：a）确定俄亥俄州西奥托县和伊利诺伊州斯特林市已确定的管道源材料，以及B）采购catlinite，一种在文献中一直被错误识别的红色管道石。catlinite的问题有两个关键组成部分：定义catlinite组成的变化范围，无论是来源之间，并在一个单一的来源，如管道石国家纪念碑，明尼苏达州;并确定catlinite使用的史前和历史时期的美洲原住民的程度。由于博物馆藏品中的许多文物从未经过PIMA或XRD测试，该团队的目标是大大扩展管道和雕像的成分数据库，并确定以前没有记录的管道石和catlinites的新的本地来源。这一结果将从根本上改变东部林地的长途贸易和贵重物品交换的局面。

With National Science Foundation support, Dr. Sarah Wisseman and her colleagues employ a small, Portable Infrared Mineral Analyzer (PIMA) to locate the sources of stone materials used to make pipes and figurines dating to the Middle Woodland (ca. 50 B.C. to A.D. 250) period and later in the eastern United States. This project unites archaeologists and geologists to better define the nature of materials used by prehistoric and historic societies in the Midwest and the relationships between raw material sources, production patterns, and trade of finished artifacts. The PIMA spectrometer is an accurate and precise addition to modern analytical instruments, with the advantages that it is easy to operate, fast (30 seconds per reading), and totally non-destructive. The PIMA is equally useable in field or museum settings, and has been successfully used to determine mineral composition and likely source of valuable artifacts that cannot be destructively sampled. For example, PIMA readings were taken of a museum figurine thought to be from Mississippi, but with no documentation of provenance. Surprisingly, analysis showed a good match with flint clay from quarries in eastern Missouri, known from the team's previous work as the source of most of the Middle Mississippian (ca. A.D. 1000 to 1400) "red goddess" figurines found at or near the site of Cahokia in East St. Louis. In another example, PIMA readings confirm a local source of pipestone for Hopewellian (Middle Woodland) pipes found in northern Illinois, negating the earlier theory that all such pipes were manufactured in Ohio and then traded to the west. The PIMA technique is complementary to X-ray diffraction (XRD), a well-established laboratory technique that is used by the team to check and refine compositional readings. The research team is using both techniques to build a reference database of stone materials specific to the Midwest. The current project will focus on a) identification of source materials for pipes beyond those already identified in Scioto County, Ohio and Sterling, Illinois, and b) sourcing catlinite, a red pipestone that has been consistently misidentified in the literature. The catlinite problem has two key components: defining the range of variation of catlinite composition, both between sources and within a single source such as Pipestone National Monument, MN; and determining the extent of catlinite use by prehistoric and historic period Native Americans. Since many artifacts in museum collections have never been tested by either PIMA or XRD, the team's goal is to vastly expand the compositional database for pipes and figurines and to identify new, local sources of pipestones and catlinites that have not previously been documented. The results will radically alter the picture of long-distance trade and exchange of prestige items in the Eastern Woodlands.