The
Island of Gems
Gem
stones of Sri
Lanka are many and
varied, some rare and precious, others considered
semi precious but equally beautiful.
Sri
Lankan gem stones are found in alluvial
deposits of old river beds which have been
covered by centuries of over lay from the
eroding of the surrounding hills. The most
famous mining areas are situated on the
downward slopes of the central hills in
the southeast of the islands.
Gems occur below alluvial deposits in gem
containing gravel known as ‘illam’ which
lay buried and are approached by digging
out small vertical pits and horizontal shafts.
Precautions have to be taken to make the
mine shafts waterproof and have pumps to
drain the seeping water. The gem bearing
gravel is sent up to the surface and washed
to bring forth the precious minerals which
being heavier tend to seek the bottom of
the baskets used in the washing process.
Rough gems look like all other
pebbles and require experience and luck
to be recognized for their value. When cut
and polished they become ‘gem stones’ fit
to be set into jewellery and other ornamental
items.
Most
abundant of the local semi precious stones
are Garnet, Zircon, Tourmaline, Beryl, Topaz
and Quartz. The precious stones are Sapphire,
Ruby and Chrysoberyl family which are also
known as Alexandrite and Cat’s Eye. |
|
|
|
|
Sapphire
and Ruby
Sapphires
and Rubies belong to the hard mineral family
corundum with hardness 9, (the second hardest next to
Diamond -10), which in good colour and flawless conditions
cut to produce high quality gems which are much sought
after and very valuable. Sapphires come in many shades
of colours. Blue
Sapphires of medium cornflower blue and darker royal
blue are the ones in demand. Rubies of dark red, the colour of pigeon
blood as they say, are the pick of their kind.
Sapphires which have the colour of sunset known as Padmarajah
or lotus colour are also rare and expensive. White
sapphires are used as a close substitute to diamonds
and in reality, more rare than diamonds. Other colours
include the Orange Sapphires, Yellow Sapphires,
Green Sapphires and Pink Sapphires.
Star
Sapphires (grey to blue colour) and Star
Rubies (pink to red colour) are cut with the bottom
left untouched and the top dome shaped ‘en cabochon’
to bring out the to bring out the six rays in star formation.
These stones have to be viewed under a point source
of light to bring out the best effect.
|
|
|
Spinel
Spinel
with hardness 8, also occurs in red and many other
shades of colours. Red spinel is very rare and the blue
could be very similar to the colour of blue sapphire.
|
|
 |
|
