The second area where sedimentary k

The second area where sedimentary kaolins are being mined and
processed is along the Capim River south of Belem in the state of Para
(Fig. 24). This Capim basin is located between the 21 and 31 parallels and
the 471 and 481 meridians just south of the equator. The kaolin layers
occur in the Ipixuna Formation of Tertiary age (Fig. 27). The kaolin deposits are found in low, slightly elevated plateaus with dissected edges
which have very little regional expression and are somewhat difficult to
distinguish (Alves, Personal communication). These low lying plateaus
range from 2 to 3km in length and width and show a difference in
elevation of 30–60m above sea level. In the basin there are two layers of
kaolin, a lower layer of relatively coarse kaolin and an upper layer of fine
kaolin. The lower layer is a soft kaolin with a particle size of 50–65%
o2 mm. This kaolin is well crystallized and electron micrographs show
many large stacks in a matrix of fairly large plates (Fig. 28). There is a
relatively low percentage of particles that are o0.5 mm which is a major
difference from the soft Cretaceous age kaolins from Georgia. The upper
kaolin layer is much finer with a particle size of 85% o2 mm or more.
Fig. 29 is an electron micrograph of the hard kaolin which shows that the
particles are very fine and appear to be somewhat rounded. The proven
reserves in the Capim basin are well over 500,000,000 tons (Alves, Personal
communication). Currently, there are two operating mines which
are producing a total annual tonnage of 1,600,000 tons. The quality of
the Capim kaolins is very good. The kaolin is mined and partially processed
at the mine sites and is then transported through pipelines to
Barcarena, a port on the Guama River, a large tributary of the Amazon
(Fig. 24), where the kaolin is prepared for slurry or dry shipment.