ery ARCHEOLOGY IN BRITISH GUIANA 139 
SURFACE: : 
Color: Exterior and interior generally tan to brown; a few sherds are a tile 
orange. On a few the interior is dark gray. 
Treatment: Both surfaces scraped during the process of erasing the coils, 
but left fairly uneven and irregular. Large particles of temper protrude 
with crackle lines around them. 
Hardness: 3-3.5. 
ForM: 
Rim: Direct with rounded, flattened, or slightly tapered lip, sometimes with 
lobes added to the edge (pl. 34, e, g, h, j; fig. 55-1) ; everted, interiorly 
thickened with a rounded lip. 
Body wall thickness: Range 3-13 mm.; majority 6-S mm. 
Body diameters: 12-42 em. 
Bases: Both jar and bowl forms have three base forms: 
A. Flat, sometimes slightly thickened, joining the side wall at an angle 
of 40 to 50 degrees. Diameter 7-16 cm. (fig. 55, A). 
Bb. Flat pedestal, 5-10 mm. high, joining the body wall at an angle of 20 
to 35 degrees. Diameter 9-10 em. (fig. 55, B). 
C. Rounded, sometimes slightly thickened at the center (fig. 55, C). 
Major vessel shapes reconstructed from sherds: 
1. Open bowls with vertical to slightly outsloping side walls, direct 
rim, and rounded or slightly tapered lip. Mouth diameter 16-34 
em. (fig. 55-1). Some have lobes dividing the rim into thirds or 
quarters. They are either plain, scalloped, or bilobed, measuring 
3-7 em. long and extending 1.0—-2.4 cm. beyond the normal lip (fig. 
55-1; pl. 34, e, g, h, j). 
2. Bowls or jars with incurving side walls, constricted mouth, direct rim 
and rounded, tapered or flattened lip. Mouth diameter 16-29 em. 
(fig. 55-2). 
3. Jars with vertical or insloping upper walls and interiorly thickened, 
everted rim with a flat rim surface usually sloping at a 45-degree 
angle to the mouth opening. Rim 1.0-3.2 cm. wide, 5-17 mm. thick, 
with rounded or flattened lip; mouth diameter 18-34 em. (fig. 55-3). 
TEMPORAL DIFFERENCES WITHIN THE TYPE: The time represented by the Koriabo 
Phase is too short and rim sherds are too few to reveal any reliable trends of 
change. However, it is possible that Base Form B, the flat pedestal, is re- 
stricted to the upper (late) part of the sequence (Appendix, table 20). 
CHRONOLOGICAL POSITION OF THE TYPE: Warapoco Plain declines in popularity 
from 58.8 percent at the earliest level in the seriation to 29.8 percent at the 
top of the sequence (fig. 57). 
TRADE SHERDS OF MABARUMA PHASE ORIGIN 
All of the Koriabo Phase sites produced sherds from vessels representing three 
plain and four decorated types of Mabaruma Phase origin. Taken together, these 
constitute 678 sherds, or 13.4 percent, of a total of 5,056 sherds from Koriabo 
Phase sites. It is probable that Mabaruma Plain is also present, but its paste 
characteristics are so similar to those of Koriabo Plain and Warapoco Plain that 
the sherds could not be separated with confidence. The trade materials (pl. 23; 
fig. 56) are in all respects typical of the Mabaruma Phase pottery types to which 
they belong (pls. 21, 26, 27) and detailed descriptions can be found under the 
Mabaruma Phase (pp. 86-113). Appendix table 16 shows the exact provenience 
513186—60——11 
