_________________________________________________________________________________ Chapter: TROUMASSOID STONE ARTIFACTS IN TOBAGO: 29 ROCK TYPES AND SOURCE AREAS Arie Boomert and Cassandra T. Rogers ________________________________________________________________________________________________ This paper discusses the rock types used for the various stone artifacts encountered at the Troumassoid sites of Golden Grove (TOB-13) and Lovers’ Retreat (TOB-69) in Tobago. It concludes that the late-prehistoric Tobagonian Amerindians ZHUH JRRG JHRORJLVWV DV WKH\ PXVW KDYH FDUHIXOO\ WHVWHG DQG VHOHFWHG VSHFL¿F URFN PDWHULDOV IRU GLIIHUHQW IXQFWLRQDO classes of implements, including cutting, grinding, pounding, rubbing, and polishing tools, as well as ornaments. Besides, investigation of the provenance areas of the various rock types used indicates that the variety of rock sources in Tobago ZDVVXI¿FLHQWO\ODUJHWRSURYLGHWKH7URXPDVVRLG,QGLDQVZLWKDOOWKHUDZPDWHULDOVWKH\QHHGHGIRUWKHPDQXIDFWXUHRI the entire spectrum of utilitarian implements they employed. This applies to most ornaments as well. In fact, it appears 282 that Tobago formed a major manufacturing site of beads made of local Tobagonian diorite throughout Troumassoid times. The few beads and pendants made of exotic rock materials recovered from the late-prehistoric sites in the island may have derived from the South American mainland. Esta ponencia trata de los tipos de roca utilizados para los diversos artefactos de piedra encontrados en los sitios WURXPDVVRLGHVGH*ROGHQ*URYH 72% \/RYHUV¶5HWUHDW 72% HQ7REDJR,QGLFDTXHORVDPHULQGLRVWREDJXHQVHV GHOSHUtRGRSUHKLVWyULFRWDUGtRHUDQEXHQRVJHyORJRVTXHGHELHURQKDEHUH[DPLQDGR\VHOHFFLRQDGRFXLGDGRVDPHQWHORV PDWHULDOHVURFRVRVSDUDGLIHUHQWHVFODVHVGHXWHQVLOLRVIXQFLRQDOHVLQFOX\HQGRKHUUDPLHQWDVSDUDFRUWDUD¿ODUJROSHDU IULFFLRQDU\SXOLUDVtFRPRRUQDPHQWRV$GHPiVODLQYHVWLJDFLyQGHODViUHDVGHSURFHGHQFLDGHORVGLYHUVRVWLSRVGH URFDXVDGRVLQGLFDTXHODYDULHGDGGHODVIXHQWHVGHURFDHQ7REDJRIXHORVX¿FLHQWHPHQWHH[WHQVDFRPRSDUDSURYHHU DORVLQGLRVWURXPDVVRLGHVGHWRGDVODVPDWHULDVSULPDVTXHQHFHVLWDEDQSDUDODIDEULFDFLyQGHODJDPDFRPSOHWDGHORV XWHQVLOLRVXWLOLWDULRVTXHHPSOHDEDQ(VWRWDPELpQVHDSOLFDDODPD\RUtDGHORVRUQDPHQWRV'HKHFKRSDUHFHTXH7REDJR IXHXQVLWLRLPSRUWDQWHGHIDEULFDFLyQGHFXHQWDVKHFKDVGHGLRULWDORFDOHQWRGRHOSHUtRGR7URXPDVVRLGH/DVSRFDV FXHQWDV\FROJDQWHVKHFKRVGHPDWHULDOHVURFRVRVH[yWLFRVUHFXSHUDGRVGHORVVLWLRVSUHKLVWyULFRVWDUGtRVHQODLVODSXHGHQ haber provenido del continente sur americano. Cette communication discute les types de roches utilisées dans les divers artéfacts en pierre retrouvés sur les sites WURXPDVVRwGHV GH *ROGHQ *URYH 72% HW /RYHU¶V 5HWUHDW 72% j 7REDJR2Q D FRQFOX TXH OHV $PpULQGLHQV WREDJRQLHQVGHODUpFHQWHSpULRGHSUpKLVWRULTXHpWDLHQWGHERQVJpRORJXHVLOVRQWGHVVD\HUHWVpOHFWLRQQHUDYHFVRLQ OHPDWpULHOURFKHX[VSpFL¿TXHSRXUGLIIpUHQWHVVRUWHVG¶XVWHQVLOHVVHORQOHXUVIRQFWLRQV\FRPSULVGHVRXWLOVSRXUFRXSHU PRXGUHFRJQHUGXUIURWWHUHWSROLUGHPrPHTXHGHVRUQHPHQWV(QRXWUHGHVUHFKHUFKHVVXUODSURYHQDQFHGHVGLIIpUHQWV W\SHVGHURFKHVXWLOLVpHVLQGLTXHQWTXHODGLYHUVLWpGHVVRXUFHVGHURFKHVj7REDJRpWDLWDVVH]JUDQGHSRXURIIULUDX[ ,QGLHQVWURXPDVVRwGHVWRXWHVOHVPDWLqUHVSUHPLqUHVGRQWLOVDYDLHQWEHVRLQSRXUIDEULTXHUODODUJHJDPPHG¶XVWHQVLOHV TX¶LOVXWLOLVDLHQW&HFLV¶DSSOLTXHDXVVLjWRXVOHVRUQHPHQWV(QIDLWLOVHPEOHTXH7REDJRDpWpXQVLWHSULQFLSDOGH IDEULFDWLRQGHSHUOHVIDLWHVHQGLRULWHORFDOHGH7REDJRSHQGDQWWRXWHODSpULRGH7URXPDVVRwGH/HVTXHOTXHVSHUOHVHW SHQGHQWLIVIDLWVHQSLHUUHH[RWLTXHTXHO¶RQDUpFROWpVGHVVLWHVGHODUpFHQWHSpULRGHSUpKLVWRULTXHVXUO¶vOHRQWGSURYHQLU GXFRQWLQHQWGHO¶$PpULTXHGX6XG _________________________________________________________________________________ Introduction In the Caribbean, systematic and comprehensive petrographic analyses of pre-Columbian stone DUWLIDFWVZHUH¿UVWFRQGXFWHGLQWKHVQRWDEO\E\5RRERODQG/HH DQGVXEVHTXHQWO\E\ Boomert and Kroonenberg (1977) on materials from Jamaica and Suriname, respectively. Since then, studies involving macroscopical and microscopical investigation of the samples as well as thin-section DQDO\VHVDQGJHRFKHPLFDOVWXG\WKURXJK;UD\ÀXRUHVFHQFH ;5) VSHFWURPHWU\DQGRWKHUPHWKRGV have been pursued in the region by Fandrich (1991) on prehistoric stone implements from Grenada. Watters and Scaglion (1994), Haviser (1999), Murphy et al. (2000) and Knippenberg (2004) have also conducted research on various materials, including utilitarian and non-utilitarian artifacts from the Leeward Islands. The analytical methods used and procedures followed in these and comparable VWXGLHVRIOLWKLFLGHQWL¿FDWLRQDQGVRXUFLQJDUHVXPPDUL]HGE\7\NRW This paper discusses the Troumassoid stone artifact categories from Tobago and the rock types used for their manufacture. It has two major aims. Firstly, it seeks to establish the provenance areas RIWKHYDULRXVURFNPDWHULDOVHPSOR\HGVRDVWRJHWLQVLJKWLQWRWKHH[WHQWRIORFDOSURFXUHPHQWDQG TXDUU\LQJYHUVXVH[FKDQJHDQGDFTXLVLWLRQRIIRUHLJQUDZPDWHULDOVRU¿QLVKHGSURGXFWV6HFRQGO\WKH SDSHUVHHNVWRGHWHUPLQHWKHSRVVLEOHDVVRFLDWLRQVEHWZHHQVSHFL¿FDUWLIDFWFODVVHVDQGURFNW\SHVLQ relation to the stone implements and ornaments in prehistoric Suriname. As Boomert & Kroonenberg (1977) were able to show, during late-prehistoric times, the Amerindian communities of the stoneless FRDVWDOSODLQRI6XULQDPHGHSHQGHGRQVWRQHD[HKHDGVDQGRWKHUFXWWLQJWRROVH[FKDQJHGZLWK,QGLDQV RIDGLVWLQFWFHUDPLFFRPSOH[FRQFHQWUDWHGLQWKHFHQWUDOHDVWHUQSDUWRIWKHFRXQWU\7KLV%URZQVEHUJ 283 FRPSOH[DSSDUHQWO\VSHFLDOL]HGLQWKHPDQXIDFWXUHRIVXFKLPSOHPHQWVXVLQJDQHVSHFLDOO\VXLWDEOH LJQHRXVURFNW\SHLHPHWDEDVDOWZKLFKLVRIUHVWULFWHGRFFXUUHQFHLQWKHUHJLRQ7KHVRFLDOFRQWH[WV RIPHWDEDVDOWTXDUU\LQJD[HKHDGSURGXFWLRQDQGGLVWULEXWLRQPD\EHFRPSDUHGWRWKRVHRIVLPLODUO\ highly valued rock types among tribal peoples elsewhere in the world (e.g., Bradley & Edmonds 1993; McBryde 1984; ToUUHQFHņ:KLWH 0RGMHVND Geological Make-up of Tobago 7KHVDPSOHRI7REDJRQLDQVWRQHDUWLIDFWVH[DPLQHGFRQVLVWVRIVSHFLPHQVHQFRXQWHUHGDWWKH Troumassoid settlement sites of Golden Grove (TOB-13) and Lovers’ Retreat (TOB-69) respectively, both situated in the southwest of the island (Figure 1). The Golden Grove site yielded ceramics of the ROGHVW7URXPDVVRLGDVVHPEODJHRI7REDJRZLWKWKH*ROGHQ*URYHFRPSOH[LQLWVXSSHUOHYHOVLH 6WUDWD,9ņ9 GRZQWRDGHSWKRIFPEHORZWKHSUHVHQWVXUIDFH VXSHULPSRVLQJ6DODGRLGUHIXVH 7KHVSHFLPHQVVWRQHDUWLIDFWVDQDO\VHGZHUHH[FDYDWHGDWWKHVLWHLQDQGE\3HWHU2¶% +DUULVDQGWKH¿UVWDXWKRUUHVSHFWLYHO\ +DUULV%RRPHUW±QG 7KHVLWHRI/RYHUV¶ 5HWUHDW6HFWLRQ&\LHOGHGLQDWRWDORIDUWLIDFWVDVVRFLDWHGZLWKWKH3O\PRXWKFRPSOH[LHWKH \RXQJHVW7URXPDVVRLGFRPSOH[RIWKHLVODQG7KH\ZHUHUHFRYHUHGIURPWKHVLWHE\3HWHU2¶%ULHQ +DUULVLQDQGE\WKHDXWKRULQņDQG %RRPHUWņ+DUULV 7KH WRWDO VDPSOH RI DUWLIDFWV DSSHDUHG WR HQFRPSDVV DOO ¿IWHHQ URFN W\SHV LQFOXGLQJ metamorphic, igneous and sedimentary rocks. All of these are locally available in Tobago which JHRORJLFDOO\VKRZVDQXPEHURIGLVWLQFW]RQHVFKDUDFWHUL]HGE\VSHFL¿FFODVVHVRIURFNVDQGPLQHUDOV The island forms part of the northeasternmost corner of the present-day South American continental VKHOI,WKDVDI¿QLWLHVZLWKD&UHWDFHRXVRFHDQLFDUFV\VWHPDQGLVSDUWRIDQDOORFKWKRQRXVWHUUDQH within the South American-Caribbean plate boundary zone to which North Trinidad and the Venezuelan Coastal Cordillera also belong. Tobago consists of two major physiographic units, i.e., the Main Ridge, a heavily dissected central dorsal ridge of highland, which forms the backbone of the island, and the Coral Lowlands, an elongated coral limestone platform adjoining the foothills of the Main Ridge to the southwest. The Main Ridge is Tobago’s major divide, reaching up to 565 m above Mean Sea Level (MSL). Three east-west striking lithologic belts, dating from Cretaceous times, transect Tobago’s Main Ridge IURPQRUWKWRVRXWKDVIROORZV¿UVWO\WKH1RUWK&RDVW6FKLVWVHFRQGO\DQXOWUDPD¿FWRWRQDOLWKLF plutonic suite, and, thirdly, the Tobago Volcanic Group (Figure 2). The North Coast Schist comprises low-grade, metamorphosed volcanogenic rocks such as metatuffs, tuffs, tuff breccias, argillites, greenschists, sericite schists, phyllites, and metacherts. The south and east of this belt of metamorphic URFNVDUHÀDQNHGE\FRPSOH[HVRIXOWUDPD¿FWRWRQDOLWKLFLQWUXVLYHVDGMRLQHGE\DQH[WHQGHGEDWKROLWK of sheared and weathered diorite which outcrops as a broad zone across the central and eastern part of Tobago. The foothills of the Main Ridge, south and east of the diorite belt, are made up of igneous volcanic rocks, including tuffs, breccias, dacites, andesites and basalts (Snoke et al. 2001). Towards the southwest, the Tobago Volcanic Group is bounded by Quaternary coralline limestone deposits, at a few locations displaced by the soft sedimentary rocks, including fossiliferous clays, marls and sands, of the Pliocene Rockly Bay Formation and Plio-Pleistocene sandstones, conglomerates and limestones (Persad 1984; Snoke et al. 2001). Coral limestone is found from a low bench at the seashore to about 35 m above MSL on top of a diorite sea cliff at Culloden on Tobago’s ZHVWFRDVW/LYHFRUDOJURZVRIIVKRUHHYHU\ZKHUHDURXQGWKHLVODQGH[FHSWIRUWKHHDVWHUQ ZLQGZDUG shore. The Coral Lowlands, consisting of two level platforms situated at 3.5 and 7.5 m respectively above MSL, represent two stages in the Pleistocene uplift of the island (Niddrie 1980: 27, 30–32). 284 Troumassoid Rock Types and Source Areas Both the Golden Grove and the Lovers’ Retreat sites yielded artifacts predominantly comprising igneous rocks, i.e., rhyolite, andesite, basalt, dolerite, and diorite (77.3% and 48.3%, respectively), and fewer specimens of metamorphic rocks, i.e., greenstone, greenschist, sericite schist, serpentinite, quartzite, and metaconglomerate (14.7% and 36.2%). Only a small number of artifacts are manufactured