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Exploration and Mining in Greenland
GEOLOGY AND ORE
No. 7 - January 2007
GEMSTONES
of GREENLAND
GEMSTONES
of GREENLAND
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Renewed focus on Greenland gem-
stones has been experienced since
the turn of the century.
Two gemstone companies have
demonstrated solid and continued
interest in the potential of classical
gemstones in Greenland in this peri-
od. Diamonds and rubies are defi-
nitely now in focus with the size of
diamonds growing almost with every
new exploration event. The largest
diamond to date has just been report-
ed at 0.122 carats.
Rubies and pink sapphires are now
at hand with large, high-quality stones
in faceting as well as in carving types.
Exploration activity targeted at both
commodities may be approaching the
next stage, with pre-feasibility studies
and production considerations. A
number of other species of coloured
gemstones and generally lower-
priced semi-precious gem material
have also been found, and these are
often very much in demand locally as
well as internationally. Well-known
examples are kornerupine, tugtupite,
lazurite and amazonite. Several multi-
coloured rock types have been pro-
duced on a small scale locally for many
years and have gained high popularity
among tourists and collectors, with
the famous nuummite, greenlandite
and `ice blue' chalcedony being the
most favoured.
A number of additional classical coloured
gemstones such as beryl, cordierite, peri-
dote, tourmaline, garnet, spinel and topaz
are known from scattered occurrences,
but their potential has never been tested.
The variety in the Greenland geological
environment, not least the pegmatite
occurrence, is definite justification for more
systematic exploration for such stones.
Exploration
Diamonds are well-known from the 600 Ma
old North Atlantic province of carbonatites
and ultramafic alkaline magmatism in
southern West Greenland, which has been
a target for commercial exploration since
the mid-1990s. SOFar this has resulted in
numerous finds of ultramafic lamprophyre
and kimberlite dykes and micro/macro dia-
monds have been recovered from many of
these rocks. All work by active companies
is still at the exploration stage.
On 24 October 2006 Hudson Resources
Inc. announced the diamond results of the
2006 exploration drill core program. The
highlight was the recovery of 35 diamonds,
including the largest diamond ever found
in Greenland. A sample of a 14.6 kg core
sample taken from a 4.5 m kimberlite
intercept in the Garnet Lake dyke in the
Sarfartoq area yielded the largest stone
weighing 0.122 carats.
The Geological Survey of Denmark and
Greenland (GEUS) recently published a
new digital compilation of all the diamond
exploration data gathered to date. This
compilation is the common knowledge base
for diamond exploration in West Green-
land. The compilation (on DVD) contains:
· 164 scanned reports in Adobe PDF
documents from company reports sub-
mitted to the Bureau of Minerals and
Petroleum. There are approximately 96
150 mineral analyses from 15 295
samples of till or stream sediment cov-
ering 4563 localities.
· 2780 mineral analyses representing 31
kimberlitic rock samples.
· 560 classification diagrams on which
analysed kimberlite indicator mineral
grains have been classified and plotted.
All mineral chemistry data have been
examined.
· All available geophysical maps. These
have been scanned in large format, and
are presented in Adobe PDF documents.
· Approx. 2700 observations of kimber-
litic rocks.
· Topographic data at 1:100 000 scale
for the regions of diamond exploration
as at 2004.
2
Sisimiut
Maniitsoq
Kangerlussuaq
Qaqqaarsuk
Tupertalik
Majuagaa
Sarfartoq
50 km
Kimberlitic occurrence
Diamond occurrence
Southern boundary of
Palaeoproterozoic
deformation
65°N
66°N
67°N
50°W
51°W
53°W
52°W
Greenland
Diamond occurrences in
southern West
Greenland .
Colourless and pinkish diamonds from
Garnet Lake.
Gemstones of greenland
Diamonds
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Potential
The Greenland diamond potential is con-
centrated in swarms of ultramafic dykes in
the Sisimiut­Sarfartoq­Maniitsoq region in
southern West Greenland. Fieldwork in
2006 resulted in the recognition of much
larger kimberlite dyke systems in the
Maniitsoq area than had previously been
reported. The Majuagaa dyke in this area
is a diamond-bearing and phlogopite-poor
ultramafic dyke, which is considered an
archetypical kimberlite. The number and
size of finds combined with the knowl-
edge of existence of true kimberlites sup-
ports expectations of a reasonable poten-
tial for diamonds in the province.
In the Sarfartoq area the 2006 results
illustrate the highly diamondiferous nature
and coarse diamond distribution of the
kimberlite dyke at Garnet Lake in the
Sarfartoq area. To date, a total of 357kg
of kimberlite from the Garnet Lake dyke
has yielded nine commercial-sized stones
(+0.85mm) totalling 0.31 carats or a nomi-
nal 0.87 carats/tonne. Similarly, the drilling
results confirm the Garnet Lake dyke as
being a significantly diamondiferous body,
which can be followed over a strike length
of 900 m, with 450 m down-dip.
Many of the kimberlite localities in the
Maniitsoq area contain abundant dia-
mond-favourable peridotitic and eclogitic
garnets, along with diamond-favourable
chromites and clinopyroxenes. Mineral
chemistry data for these occurrences,
along with several occurrences in the
Sarfartoq area, became available only
recently, and it is now possible to address
the provenance of the indicator minerals
from till and stream sediment.
In the field area just east of Maniitsoq,
around the mountain Sillissannguit, new
dykes with a combined length of more
than 10 km were found in 2006, and in
another area, Timitta Tasersua East near
the coast, a system of what is believed to
be one of the largest kimberlite dyke
exposures known in Greenland was found
in a steep gully above a stream with
numerous large boulders of kimberlite.
Most of the dyke systems in the Maniitsoq
area are expected to be archetypical kim-
berlites.
Quality
Quality evaluation of the huge amount
(more than 1000) of micro and macro dia-
monds recovered to date from Greenland
is scarce. However, the quality of the dia-
monds recovered from the Garnet Lake
area at Sarfartoq has undergone prelimi-
nary evaluation by the Hudson Resources
company. The recovered stones typically
have good colour (colourless to pink) and
shape (octahedron). The pink diamonds
are always of interest to the gem industry,
as noted by the company at the presenta-
tion.
3
GEMSTONES OF GREENLAND
The Majuagaa kimberlite dyke in the Maniitsoq area.
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Exploration
The first rubies were discovered in the West
Greenland region of Fiskenæsset/Qeqer-
tarsuatsiaat in 1966 on a small island, sub-
sequently named Ruby Island. In the late
1970s and early 1980s Greenland rubies
caught commercial interest. Prospecting of
ruby-bearing zones, mapping and bulk
sampling was carried out by the Canadian
exploration company Platinomino A/S.
Shortly after the turn of the century the
Greenland rubies captured renewed com-
mercial interest from Brereton Engineering
& Developments Ltd. with True North
Gems Inc. as operator.
Detailed exploration for rubies was
conducted by Platinomino A/S in the 1980s.
Detailed mapping of the Siggartartulik
zone was made and prospective zones in
that area were scrutinised. As a result of
this, several new ruby-bearing zones were
discovered. However, only limited further
work was done within the concession and
the activity ceased after a couple of years.
In 2004 True North Gems Inc. obtained
an exclusive exploration licence of a 3600
km
2
area and commenced prospecting in
the area. In 2005 True North collected 3
tonnes of mini bulk samples at five differ-
ent localities. The ruby ore was processed
at various laboratories in Canada, the UK
and Germany. The rubies were sorted into
three quality classes: gem (transparent and
semitransparent), near-gem (translucent and
semi-translucent) and non-gem (opaque).
Another ruby showing at Aappaluttoq
yielded 533 grams of gem including a 20-
gram single stone, all derived from a 100-
kilo outcrop sample.
In 2006 True North concentrated their
efforts on the two most promising ruby
localities discovered to date: Aappaluttoq
and Kigutilik. A 30-tonne bulk sample was
collected from each of the two sites. Much
of the sampling was carried out by dia-
mond-tipped chain saws and samples
were flown tOFiskenæsset, where a small
processing plant was established. The rocks
were gently crushed and the heavy miner-
als were separated. The ruby concentrates
were hand-picked for the largest, best
quality rubies.
Prospecting of the area surrounding
Aappaluttoq led to the discovery of a band
of multiple ruby-bearing horizons, extend-
ing for 2 km from the historic locality of
Ruby Island to Aappaluttoq. This region
will be the focus of planned diamond
drilling in the future.
Geological environment
The Fiskenæsset region is dominated by
extensive gneiss tracts with enclaves of
greenstone belts. A large, layered anortho-
4
560000 mE
540000 mE
520000 mE
Ivnaarssuunguaq
Ivnaarssuunguaq
Qaqat Aqulerit
Qaqat Aqulerit
Qaqqatsiaq
Qaqqatsiaq
Tuk
Tuk
Ivnaarssuunguaq
Kaadaaq
Northwest Annertusoq
Upper Annertusoq East Extension
Upper Annertusoq
Lichtenfels
Lower Annertusoq
Kigutilik
Pupiq
Altiplano 001
Siggartartulik
Laks Elv
Nugussup Qavat
Puilassut Qavat
Rejane's Occurrence
Sarfaq
Aappaluttoq
Ridgetop
Mikisoq
Tassiusa Gate
Tasiusarsuaq Waterline
Ruby Island (Tasiusarsuaq)
Sungasa Nuat
Kaadaaq
Northwest Annertusoq
Upper Annertusoq East Extension
Upper Annertusoq
Lichtenfels
Lower Annertusoq
Kigutilik
Kangarssuk
Kangarssuk
Pupiq
Altiplano 001
Siggartartulik
Laks Elv
Nugussup Qavat
Puilassut Qavat
Rejane's Occurrence
Sarfaq
Aappaluttoq
Ridgetop
Mikisoq
Tassiusa Gate
Tasiusarsuaq Waterline
Ruby Island (Tasiusarsuaq)
Qaqat Aqulerit
Qaqqatsiaq
Sungasa Nuat
Tuk
Qororssuaq
Bjornesund
Qororssuaq
Pikiniq
Pikiniq
Pikiniq
Bjornesund
GREENLAND
Fiskenaesset Project
8
True North Gems
0
2
4
kilometres
RUBY OCCURRENCES
Surface Plan
Scale: 1:200000
Drawing:
Projection: UTM Zone 22, Northern Hemisphere (WGS 84)
Date:28/11/2006
Author: B. Weston
Office: Vancouver
Greenland
GEMSTONES OF GREENLAND
Map of ruby occurrences in the Fiskenæsset area. Courtesy: True North.
Rubies and pink sapphires
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site complex with a total length of more
than 200 km intruded into pillow-struc-
tured amphibolites in the greenstone belts.
The Fiskenæsset complex comprises
anorthosites, gabbros and utrabasic rocks.
Minor components are banded chromitites
which are up to a few tens of metres in
thickness and can be traced at intervals
for many kilometres. The region has been
repeatedly deformed and metamorphosed
under amphibolite facies, locally up to
granulite facies conditions.
The ruby-bearing rocks are very distinct
and often revealed by the abundance of
bright green tschermakite amphibole. The
mineral assemblage comprises red corun-
dum, red spinel, sapphirine, kyanite, korne-
rupine and tourmaline in a groundmass of
tschermakite, phlogopite, anorthite and
dolomite. These minerals occur in different
proportions. The ruby-bearing zones always
occur either at or close to the contact
between anorthosite and amphibolite/ultra-
basite. Since the anorthosites stand out
with no vegetation due to rapid weather-
ing, it is fairly easy to prospect the region
for ruby occurrences.
Ruby showings vary considerably in size
from a few square metres in outcrop to
about ten metres in width and traceable for
more than a hundred metres. The largest
ruby showing is the so-called Siggartartulik
showing and several tonnes of ruby-bear-
ing material have been extracted from this
locality.
Ruby occurrences have also been record-
ed elsewhere in West Greenland, although
only very limited prospecting for ruby-
bearing rocks has been carried out. In the
inland area east of Nuuk extensive anortho-
site bodies have been found including sev-
eral ruby showings. Most of these occur
near the contact between anorthosite and
amphibolite/ultrabasite. One of the show-
ings is on Storø, where up to 10 cm large
euhedral barrel-shaped crystals have been
found in a biotite matrix. These rubies are
red but neither transparent nor translu-
cent. In areas close to the Inland Ice rubies
have been found in similar environments.
Near Maniitsoq north of Nuuk, red
corundum crystals have been found. They
have developed as barrel-shaped crystals,
often very large (up to 1 kg) and embedded
in biotite and thus easy to release. The
colour is, however, not quite as intense the
other material described above.
Considering the close geological resem-
blance between the Fiskenæsset region and
the area further north, it seems appropri-
ate to assume that the ruby-potential near
Nuuk and further north is promising.
Gem types and processing
The coloured gems sOFar recovered have
been classified as rubies and pink sap-
phires. In 2005 True North established a
small cutting and polishing centre in the
village of Fiskenæsset in order to teach
the local residents how to cut and polish
cabochons of ruby. In the early spring
2006 a team of teachers and machinery
were introduced for courses in faceting
rubies. The courses were successful and
some of the residents proved to have the
potential for faceting gem stones.
A piece of ruby rough discovered in
2005, approximately 4 cm x 5.5 cm with a
maximum thickness of 3 cm, has been
graded as near-gem with gem segments.
The material is a polycrystaline form, dis-
playing good natural red colouration
throughout, with mostly translucent to
near-transparent sections. This gem piece
has been carved yielding a stone of 302
carat which is estimated to have a value
of around 1.5 million CAD.
True North has carried out a number of
beneficiation tests on the rubies, some
using automated optical sorting devices
originally constructed to separate reusable
glass. Tests have also been made to heat-
treat fractured and very pale rubies in
order to obtain better colour and less frac-
tures. The results are promising and the
activity in the Fiskenæsset region is proba-
bly approaching the exploitation stage.
5
GEMSTONES OF GREENLAND
Canadian gem cutting expert Brad Wilson
demonstrates the faceting equipment in
Fiskenæsset. Courtesy: True North.
Rubies from Aappaluttoq. From left to right, stones weigh 0.43, 0.42, 0.77, 0.43, and 0.22
carats. Courtesy: True North.
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6
Cluster of ruby crystals, Fiskenæsset, West
Greenland. Size of cluster: 2,8 x 4, 2 cm.
Courtesy: Geological Museum.
GEMSTONES OF GREENLAND
background image
Kornerupine
Kornerupine has been known since 1884,
when the mineral was found and described
from a locality near Qeqertarsuatsiaat
(Fiskenæsset). The mineral was hosted in a
sequence of anorthosite within the folded
chromite-anorthosite igneous complex of
the area. Kornerupine is associated with a
suite of spectacular minerals such as sap-
phirine, ruby, cordierite, tschermakite,
spinel and tourmaline. The normal shape
of kornerupine is radiating aggregates but
locally single crystals with a distinctly pris-
matic habit have developed. In 1975 a new
site in the area delivered giant crystals of
kornerupine measuring up to 23 cm (9 inch)
in length.
The usual colour of the mineral from
the West Greenland area is greyish-green-
ish with a brownish tint and with a non-
transparent appearance. The giant crystals
display a clear blue-green colour, scattered
with smaller areas with sufficient clarity
and freedom from flaws to allow faceted
gems to be made. Altogether 21 stones
were cut from this material, including 14
faceted gems and 7 cabochons. The
largest examples of 5.88 and 1.72 carats
are displayed at the Geological Museum
of Copenhagen. The material has never
been traded or otherwise commercially
tested.
Although none of the faceted exam-
ples are completely flawless, the clear
colour and the pleochromism from dark
green to light blue is convincing and ren-
ders the Greenland kornerupine with
promising possibilities as an attractive
coloured stone. The number of localities is
rather limited and until 1975 only the type
specimens from 1884 were known.
However, the find of the single crystals
points to a potential for new finds.
Tugtupite
Tugtupite was introduced as a new miner-
al from Greenland in 1965. However, it
was discovered as early as 1957 at a site
along the shore of the Tunulliarfik fjord in
South Greenland. Material from the locali-
ty was described as white and it was men-
tioned that the colour changes to pale
7
GEMSTONES OF GREENLAND
Above: Faceted kornerupine from the
Fiskenæsset area. Stones of 1.72 ct (top) and
0.68 ct (bottom). Courtesy: Geological
Museum.
Left: Giant kornerupine crystal (23 cm in
length) from the Fiskenæsset area. Courtesy:
Geological Museum.
Exploitation of other gemstones
Below: Rough sample of tugtupite in vein
with white albite and brown spahlerite from
the Narsaq area. Size of sample: 8 x 10 cm.
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pink after exposure to daylight. In 1965
the tugtupite with a dark crimson red
colour was found on the Kvanefjeld
mountain near the town of Narsaq, and
since then this strong coloured type has
been the most sought after by collectors
and tourists. A light blue variety is also
known from this locality. Tugtupite is
found within the peralkaline igneous
Ilimaussaq Intrusion and it is confined to
late hydrothermal veins, often associated
with albite, analcime, aegirine, sphalerite,
neptunite and pyrochlore. Most tugtupite
is massive, and developed crystals are
extremely rare. Since the presentation in
1965, several new showings have been
discovered in the area. Many of these
have been emptied and to day proper
showings of tugtupite albite veins are
hard tOFind.
As tugtupite is typically found in mas-
sive, polycrystalline pieces, the typical cut
of the stone has been as cabochons or as
shaped pieces, intended for mounting in
precious metal frames. Tugtupite is mostly
cut and polished by local craftsmen in a
kind of lapidary home industry. The cabo-
chons are sold by local dealers and in
tourist shops and in airports. The mineral
is well known outside Greenland and also
traded internationally at jewellers and at
trade shows. The potential for larger pro-
duction is limited. The area with the
known occurrence is small and on top of
this the local municipality has issued
administrative regulations concerning
commercial collecting.
Tugtupite has gained a reputation as
the Greenland gemstone par excellence.
The colour change from red to pink or
white and back to red after being exposed
to daylight (or ultraviolet radiation) after
being in the dark (in the jewel case), is
more of a curiosity, not known in other
gemstones, and maybe not really a mar-
keting issue. On the other hand tugtupite
is renowned for its intense glowing dark
red fluorescence, when it is exposed to
short-wave UV-light. Accurate pricing of
tugtupite is difficult to obtain because of
the great range of quality from different
showings, however, it is one of the high-
est priced Greenland stones.
Lapis lazuli
Around 60 km east of the town of
Maniitsoq at a locality named Tupertalik
after the 980 m a.s.l. mountain nearby,
lapis lazuli (lazurite) has been known since
the 1960s. At that time the area was
being prospected by Kryolitselskabet
Øresund A/S, which did not find it of
commercial interest. The locality was sam-
pled and mapped in 1979 and 1981 by
GEUS. After that time local lapidarians
showed some interest in the area. It is
located along the margin of a slightly
folded and metamorphosed Archaean car-
bonatite sheet within the basement. As a
result of reaction between the carbonatite
and the basement gneisses, new minerals
such as skapolite and lazurite have devel-
oped. The skapolite is white and the lazu-
rite is pale ultramarine blue, and therefore
pieces cut from the material have the
characteristic combination of blue ground-
mass with irregular white spots. Specks of
sulphides are never found in Greenland
material. The size of the carbonatite is
around 200 x 500 m, which represents
the surface exposure of the margins of the
slightly folded sheet. Lazurite from
GEMSTONES OF GREENLAND
8
Cabochon cut tugtupite from the Narsaq
area. Largest cabochon: 2.5 cm.
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Greenland is only known from this locality.
Lazurite is normally observed cut and
polished by local craftsmen in a kind of
lapidary home industry. Chacochons and
plane polished slabs are most popular, typ-
ically in various mounts of silver. It is not
unusual to see jewellery where lazurite is
combined with other coloured Greenland
gemstones such as tugtupite and ama-
zonite. The potential for further finds is
limited to the size of the carbonatite
exposure. Greenland lazurite has never
been a target for commercial exploration.
One prominent use of the material is as a
part of the decoration of the neck chain
insignia of the mayor of Maniitsoq.
Amazonite
Within the Nunarssuit intrusive complex in
South Greenland a number of pegmatite
dykes have been found at several localities
in the westernmost `main granite'. The
complex is of Mid Gardar age (1150 Ma),
it is composed of suites of granites and
syenites and is located on the Nunarssuit
peninsula. The complex is well-known for
its pegmatites, often located in sequences
of microgranite. The amazonite is nicely
developed together with coarse quartz
and biotite in dykes of up to 1-2 m width.
Graphic granite is frequently seen border-
ing the pegmatites. Amazonite crystals are
up 5 x 15 cm.
Granitic pegmatites in the Tasiilaq area
of East Greenland have been reported to
contain well developed amazonite crystals,
but the colour of the Tasiilaq material is
9
GEMSTONES OF GREENLAND
Lazurite crystal from the Maniitsoq area.
Sample size: 5 x 5.5 cm. Courtesy:
Geological Museum.
Cabochon cut lazurite from the Maniitsoq
area. Size of cabochon: 2 x 4 cm.
Amazonite crystal in pegmatite from the
Nunarssuit area. Length of crystal: 15 cm.
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pale blue-green compared to the
Nunarssuit crystals.
The Nunarssuit amazonite has the
characteristic silvery internal reflections,
which are enhanced by polishing, either as
cabochons or as plane slabs. The
Nunarssuit occurrence has been quarried
for pilot uses under an exploitation license
held in 1986 by the municipality of
Qaqortoq. The municipality intended to
establish work shops in the town. Here
residents could use the material from the
quarry and learn to cut and polish gem-
stones of local heritage, so called unique
`town gemstones'. However, the initiative
was closed in 1987 after several attempts
to create treated gemstones and the quar-
ried amazonite was dispersed among
town collectors. Eventually the license was
relinquished. The potential has been eval-
uated as good, as the pegmatites are
found at several places in the area.
Nuummite
Nuummite is a gemstone formed from a
mixture of two minerals from the amphi-
bole group: anthophyllite and gedrite. The
name nuummite (meaning `from Nuuk') is
derived from the name of the Greenland
capital, Nuuk, where the stone was dis-
covered in 1982 by GEUS. Some might
claim that nuummite was in fact rediscov-
ered, since the mineralogist K.L. Giesecke
had collected similar specimens in 1810.
The two minerals are
found at several
localities in the
Nuuk area.
Nuummite is
thought to
be of volcanic
origin and was
formed about 3
billion years ago.
Metamorphic
alteration of the rock resulted in the strik-
ing mixture of crystals which gives nuum-
mite its unique appearance. Nuummite
has an overall hardness of 5_­6 and con-
stitutes a mixture of elongated crystals,
often in sheaf-like groups. In the transition
between the individual crystals (and espe-
cially the thin ones), an optical effect is
created which causes them to display a
particular `inner' golden glow, almost like
flames in a fire. This effect is known as iri-
descence, and is very distinctive on pol-
ished surfaces. The colours vary somewhat
between reddish, greenish and bluish
nuances.
Nuummite is typically treated by local
lapidarians and has created a base for a
solid home business. It is generally easy to
polish, even though it can be difficult to
avoid holes and cracks in certain
qualities of stones with
many parallel crystals.
The usual shape is
cabochon, but other
convex finishes also
produce attractive
shapes. In larger pieces
it is possible to retain most
of the colours of the irides-
cence, so that one end of
the cabochon has a golden
colour while the opposite end has a bluish
hue.
The marketing of nuummite immedi-
ately after its discovery was quite intense,
with a successful initiative to introduce it
on the international market. The munici-
pality of Nuuk carried out exploitation of
the material for a short period in the mid
1980s. The potential for finding more
showings seems to be good.
Greenlandite
The rock greenlandite (`grønlandite') was
given this grandiose, unofficial name to
GEMSTONES OF GREENLAND
Sample of rough greenlandite
from the Nuuk area. Size of
sample: 7 x 8 cm.
Cabochon cut nuummite (3.5 cm) from
the Nuuk area.
10
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11
GEMSTONES OF GREENLAND
mark Greenland's new interest in its rocks.
The stone was discovered in the 1960s
during the survey of the large iron
deposit, Isukasia north of Nuuk and it was
subsequently discovered at several locali-
ties in the Nuuk area. It was later estab-
lished that the geological environment in
which greenlandite was formed was in the
order of 3.8 billion years old. This makes it
one of the earth's oldest formations and
accordingly the oldest gemstone in the
world.
As a result of the dominant quartz with
a hardness of 7, greenlandite is fairly hard
and can readily be polished to a smooth
surface which is often done as cabochons
and plane slabs. Varying green and white
streaks in the same piece can produce
many variants of the stone. Thin slices are
partially translucent, and are therefore
well-suited to uses requiring light to pass
through. Greenlandite is also well-suited
as a dimension stone for use in decora-
tions.
Greenlandite consists of quartzite with
a green chromium-bearing mica, fuchsite,
evenly distributed throughout, giving the
stone a fresh green colour. Quartzite is
made of fine-grained quartz, while the
fuchsite resembles glitter with fine, small
spangles distributed throughout the rock.
It has a metallic inner glow deriving from
its many spangles. This type of stone is
also known among the jewellers as green
aventurine quartz, also reported from
Brazil and southern African localities.
Experts will note that the colour of green-
landite is more bluish green than the for-
eign types. The potential of finding more
raw material in Greenland is good in the
Nuuk area. There has been no attempt to
exploit greenlandite commercially sOFar.
Other semi-precious
gems
Small occurrences of other traditional
gemstones are also known in Greenland:
Beryl (bluegreen), chalcedony (red, brown,
green, blue and white), cordierite
(dichroite), feldspar (`moonstone'), garnet,
peridote (olivine), quartz (rocky, smoky,
amethyst), spinel (red), topaz (microcrys-
talline) and tourmaline (black) have been
found in sporadic showings, some of
them already popular as gem material and
others still with an unproven potential as
gems. Medium-hard minerals like cancri-
nite, natrolite, prehnite, sodalite (blue, yel-
low, green) and thulite are often used by
local lapidarians in areas where they are
familiar to the rock hounds. Like nuum-
mite and greenlandite, a number of rocks
have been polished and cabochon cut and
have gained a reputation and trade status
as unique Greenland gemstone souvenirs.
Examples are graphic granite, kakortokite
(eudialyte-rich nepheline syenite), naujaite
(pokillitic nepheline syenite), tschermakite
with ruby, and `satellitestone' (a poly-
chrome mixture of natrolite and sodalite).
Such materials probably have a steady or
slightly rising potential within a local
home handicraft industry.
Concluding remarks
Greenland gemstones have played a quiet
but important role as the bearer of a pub-
lic understanding of mineral exploitation.
With new opportunities for including pre-
cious gems such as diamond and ruby in
this context, mineral exploitation of gem-
stones is moving from local scale to a
much more widespread and important
mineral resource business. The potential
for such a development is certainly pos-
sible, at least based on recent exploration
results. Additionally, Greenland could
encounter more diversity in gemstone
exploration, if the obvious potential for
gem material in hard rock deposits is fully
exploited.
Majuagaa
Majuagaa
Storø
Storø
Garnet Lake
(Sarfartoq)
Qaqortoq
Ilímaussaq
Isukasia
Garnet Lake
(Sarfartoq)
Tasiilaq
Majuagaa
Storø
Qaqortoq
Nunarssuit
Ilímaussaq
Narsaq
Isukasia
Aappaluttoq
(Fiskenæsset)
Nuuk
Maniitsoq
Sisimiut
Localities for gemstones in Greenland.
background image
12
Key references
Appel, P. W. U. (1995d). "Ruby occurrences in the
Fiskenæsset area, West Greenland." Open File
Series Grønlands Geologiske Undersøgelse,
95/11 : 24.
Appel, P. W. U. and A. Jensen (1987). "A new
gem material from Greenland: iridescent orthoam-
phibole [nuummite]." Gems and Gemology, 23 :
36­42.
Bøggild, O. B. (1953). "The mineralogy of Green-
land." Meddelelser om Grønland 149,3 : 1-442.
Dragsted, O.(1970): Tugtupite. Journal of Gem-
mology 12 , 10­11
Gübelin, E. J. (1979). "Fiskenässet.. Rubinvor-
kommen auf Grönland." Lapis, 4 (3): 19­26.
Herd, R. K., B. F. Windley, et al. (1969). "The
mode of occurrence and petrogenesis of the sap-
phirine-bearing and associated rocks of West
Greenland." Rapport Grønlands Geologiske
Undersøgelse, 24 : 44.
Jensen, A. and O. V. Petersen (1982). "Tugtupite:
a gemstone from Greenland." Gems and Gem-
ology, 18 : 90­94.
Jensen, S. M., K. Secher, & Rasmussen, TM.R.
(2004). "Diamond content of three kimberlitic
occurrences in southern West Greenland. Diamond
identification results, field description and mag-
netic profiling." Danmarks og Grønlands Geo-
logiske Undersøgelse Rapport 2004/19 : 41 pp.
Jensen, S. M., K. Secher, et al. (2004). Diamond
exploration data from West Greenland: 2004
update and revision, Danmarks og Grønlands
Geologiske Undersøgelse Rapport 2004/117 : 90
+ DVD.
Myers, J. S. (1985). Stratigraphy and structure of
the Fiskenæsset Complex, southern West
Greenland. Grønlands Geologiske Undersøgelse
Bulletin 150 , 72 pp.
Nielsen, T.F.D., Jebens, M., Jensen, S.M. &
Secher, K. (2006). Archetypal kimberlite from the
Maniitsoq region, southern West Greenland and
analogy to South Africa. Geological Survey of
Denmark and Greenland Bulletin 10 , 45­48
Petersen, O. V., O. Johnsen & Jensen, A. (1980).
"Giant crystals of kornerupine." Mineralogical
Record, 11 : 93­96.
Petersen, O. V. and K. Secher (1993). "The
Minerals of Greenland." The Mineralogical Record
24,2 , 1-67.
Petersen, O. V. et al., (2002). Dravite from
Qarusulik, Ameralik Fjord in southwestern Green-
land. In: A Gemstone Spectrum. ExtraLapis English
No. 3 Tourmaline. 42­46.
Sinkankas, J. (1997). Gemstones of North
America, (Vol III). Tuscon, Arizona: Geoscience
Press, 527 pp.
Steenfelt, A., Secher, K. & Garde, A.A (in press):
An overview of pegmatite occurrences in Green-
land and their economic potential. Danmarks og
Grønlands Geologiske Undersøgelse Rapport
2007/2 .
Sørensen, H., Danø, M. & Petersen, O.V. (1971):
On the mineralogy and paragenesis of tugtupite.
Meddelelser om Grønland 181 (13), 37 pp.
Front cover photograph
Exploration for rubies at Mikisoq near
Appaluttoq. The field team examines a
ruby rich horizon. Courtesy: True North.
Bureau of Minerals and Petroleum
(BMP)
Government of Greenland
P.O. Box 930
DK-3900 Nuuk
Greenland
Tel: (+299) 34 68 00
Fax.: (+299) 32 43 02
E-mail: bmp@gh.gl
Internet: www.bmp.gl
Geological Survey of Denmark
and Greenland (GEUS)
Øster Voldgade 10
DK-1350 Copenhagen K
Denmark
Tel: (+45) 38 14 20 00
Fax.: (+45) 38 14 20 50
E-mail: geus@geus.dk
Internet: www.geus.dk
Author
K. Secher & P. Appel, GEUS
Editor
Karsten Secher, GEUS
Graphic Production
Carsten E. Thuesen, GEUS
Photographs
GEUS unless otherwise stated
Printed
January 2007 © GEUS
Printers
Schultz Grafisk
ISSN
1602-818x
A 302 carat ruby chunk
carved into various figurines.
Carved by Thomas McPhee.
Courtesy: True North.


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Last modified: January 23, 2007
MINEX is published by GEUS in co-operation with Bureau of Minerals and Petroleum, Greenland Government



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