The Earliest Inhabitants: The Dynamics of the Jamaican Taino

The results discussed here were obtained from a study of Jamaican Arawak
artefacts at the Institute of Jamaica, and others made available by members of
the Archaeological Society of Jamaica. In the first instance, a collection of
twenty-two broken petaloid tools was examined. As these proved to be
extremely fine-grained, slices were cut from them and prepared for microscopic
examination. Once the main rock types were identified with certainty,
it was possible to identify further specimens without damage, by hand or
binocular microscope examination of a wet surface. Many specimens required
scrubbing before examination to remove surface encrustation.
The Geology of Jamaica
Unlike other islands of the Greater Antilles, most of the rocks outcropping at
the surface are limestone (66.7 per cent of the area of Jamaica) containing
abundant flints. The older volcanic and metamorphic rocks that underlie the
limestone are exposed in a number of small inliers or erosional windows where
the limestone has been removed. It is mainly these older metamorphic rocks
that were used by the Jamaican Arawaks for the manufacture of their tools.
Because of the distinctive nature of different inliers of oldest rocks, it is relatively
easy in this case to trace the sources of the Arawak tools. In contrast, the
other islands of the Greater Antilles have their ancient rocks exposed over
greater areas (which also accounts for their greater mineral wealth, aside from
bauxite), so that source areas cannot be pinpointed readily.
A simplified geological map of Jamaica (Figure 9.1) is based on the provisional
geology map of Jamaica (1958). In keeping with the outline of the
Greater Antilles given here, rocks are shown only as five groups. The younger
series (post–60 million years) is divided between limestone and another group
of mainly sedimentary rocks (Wagwater conglomerate and Richmond shale)
containing some volcanic rocks (Newcastle keratophyres). The older series is
divided as follows:
1. Sediments (of volcanic debris) found mainly in the inliers at the western
end of the island.
2. A group of lavas and sediments with igneous intrusions which have not
been so altered by burial that their original characteristics are now lost; for
instance, lavas can still be distinguished from sediments. This group
occurs in the central part of the island.
3. Metamorphic rocks occurring only in the large Blue Mountains Inlier
and the tiny Green Bay inlier near Port Henderson.
The term metamorphic is used here in the sense that a sufficient portion of
the rock has recrystallized so that the original characteristics cannot be seen
P ETROGRAPHY AND S OURCE OF S OME A RAWAK R OCK A RTEFACTS FROM J AMAICA
133