Abstract:
The presence of mineral deposits along the Highland Complex (HC) -ViJayan
Complex (VC) boundary o f Sri Lanka has not yet been thoroughly studied. This study
was carried out to identify the economically important mineral deposits and rock
types along the Highland -ViJayan boundary particularly in the Wellawaya region.
The boundary between Highland Complex and ViJayan Complexes being convergent
plate boundaries is ideal for mineralization. The identification o f economic mineral
and rock occurrences hold a potential for further study of Highland - Vijayan
boundary and its mineralization.
The stream sediments samples o f Kirindi oya basin were studied. Panning, seiving,
and other heavy minerals separation methods were used to concentrate the heavy
mineral from the stream sediments. Thin section were use to study rock samples
collected from the bedrock.
The Gem minerals specially corundum, garnets and tourmaline and colour changing
garnets were found around this region. Only few localities with in-situ corundum
were found. However they are not in gem quality and not very economically valuable.
A high weight percentage o f gem-indicator mineral show the possible gem
occurrences in the vicinity.
The economic mineral deposits provide a basic for all kinds o f industrial and regional
development. All these economically important rocks and minerals such as vein
quartz, feldspar, and magnesit with large extent and the in-situ gem occurrences can
be used to increase the well being o f the society in the area around Wellawaya
