Pre-Columbian jadeitite artifacts from the Golden Rock Site, St. Eustatius, Lesser Antilles, with special reference to jadeitite artifacts from Elliot's, Antigua: Implications for potential source regions and long-distance exchange networks in the Greater Caribbean

摘要

A detailed electron microscopy analysis of jadeitite celts from the Early Ceramic Age Golden Rock settlement on the small volcanic island of St Eustatius, Lesser Antilles, is presented in an effort to identify the source region(s) of these jadeitite axes and evaluate the extent of trade networks in the Caribbean during pre-Columbian times through which those tools (or source rocks) circulated. Habitation at the site occurred between ca. AD 230-890, and the jadeitite tools most likely date between cal. AD 600 and 825/890. We argue that in provenancing jadeitite emphasis should be placed on the identification of the entire mineral assemblage (including the accessory minerals) and textures, given the complex geological histories and processes that form this quasi-monomineralic rock. Indeed, the mineral assemblages and the characteristics of the individual minerals within the studied jadeitite samples are far from homogenous, suggesting either the source has a high degree of internal variation or there are multiple sources. We have identified three jadeitite groups among the analyzed samples on the basis of mineralogical assemblages: Group 1 consists of samples bearing phlogopite (plus phengite and epidote but without lawsonite or quartz); Group 2 contains lawsonite (plus phengite and quartz but without phlogopite and epidote); and Group 3 is defined by containing hematite. Importantly, we have not identified glaucophane in the analyzed materials. The comparison of these artifact data with those of jadeitites from the four potential known source regions of Caribbean jade, i.e., Guatemala (North and South Motagua Fault mélanges), Cuba (Sierra del Convento mélange) and Dominican Republic (Río San Juan complex) allows us to conclude that both the North and South Motagua Valley mélanges are the most likely sources for artifact groups 2 and 3, and perhaps also for group 1. This identification supports earlier hypotheses on the existence of pan-regional exchange networks, tying the northern Antilles with the Isthmo-Colombian region (Colombia, Panama and Costa Rica) during the Ceramic Age of the Caribbean.