In
mid-February 2012, a new find of blue sapphires occurred southwest of
Kataragama, near the famous Yala National Park on the southeastern coast
of Sri Lanka. The sapphires were initially found on a road construction
site between Kataragama and Lunuganwehera. The soil used to cover the
road reportedly came from a small farm nearby that belonged to a Mr.
Ranga. As news of the discovery spread, thousands rushed to the area.
The Sri Lankan authorities responded swiftly and transferred 1.4
hectares of land around Mr. Ranga’s farm from the Forest Conservation
Department to the National Gems and Jewellery Authority (NGJA). The NGJA
held a February 24 auction in Kataragama for one-year mining rights on
52 individual lots.
In early March, with the support of the NGJA and some local traders,
these authors visited the site to collect samples for the GIA reference
collection. Upon reaching the deposit, located at 06°22’16″N,
81°17’18″E, we saw that it was being prepared to host an estimated 1,500
miners. Within hours the miners began arriving at their claims, and
camps sprang up from the cleared land. Miners loaded the potentially
sapphire-rich soil into bags to be taken away for washing. Only hand
tools were allowed, as mechanized mining with excavators has been
prohibited in Sri Lanka since June 2011.
At the time our expedition ended on March 9, we were unable to see
any sapphires produced from the new diggings around Mr. Ranga’s house.
However, we studied numerous samples reportedly found on the road
construction site during the initial discovery. The sapphires were
either fine crystal specimens or broken pieces with sharp edges and no
indication of alluvial transport. Fissures and cavities were filled with
a white powdery material. We saw several specimens up to 150 g and
heard reports of fine crystals as large as 300 g. Although the material
is often quite included, we expect to see some clean faceted gems
weighing more than 20 ct. Many of the crystals showed distinct dichroism
and color banding associated with layers of minute particles. Several
gem merchants onsite were excited by such Kashmir or Burma-like new
material, and at the time of our visit the asking prices were already
remarkably high.
We were unable to see any faceted stones from the new deposit,
although we expect that the combination of dichroism, color banding, and
highly visible inclusions will present challenges to cutters. More
information on the nature and extent of the new deposit will become
available after the NGJA completes its geologic survey of the area and
as mining continues.
Authors:
(1) Vincent Pardieu - GIA, Bangkok, (2) Lou Pierre Bryl –
Gaspe, Canada, (3) Andrea Heather Go - Vancouver, Canada,
(4) Boris Chauviré - Cholet, France
Source: GIA e-brief
