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GEOLOGY and ORE 7 / 2007 Diamond to Date Has Just Been Report- Southern Boundary of Palaeoproterozoic Ed at 0.122 Carats

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GEOLOGY and ORE 7 / 2007 Diamond to Date Has Just Been Report- Southern Boundary of Palaeoproterozoic Ed at 0.122 Carats GEMSTONES of GREENLAND Exploration and Mining in Greenland No. 7 - January 2007 GEOLOGY AND ORE Gemstones of greenland Renewed focus on Greenland gem- Diamond occurrences in 53°W 52°W 51°W 50°W stones has been experienced since southern West Greenland . the turn of the century. Kangerlussuaq 67°N Two gemstone companies have Sisimiut 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 Kimberlitic occurrence Sarfartoq new exploration event. The largest Diamond occurrence GEOLOGY AND ORE 7 / 2007 diamond to date has just been report- Southern boundary of Palaeoproterozoic ed at 0.122 carats. deformation 66°N Rubies and pink sapphires are now at hand with large, high-quality stones in faceting as well as in carving types. 50 km Exploration activity targeted at both commodities may be approaching the Tupertalik Qaqqaarsuk next stage, with pre-feasibility studies Maniitsoq Greenland and production considerations. A number of other species of coloured gemstones and generally lower- Majuagaa 65°N priced semi-precious gem material have also been found, and these are often very much in demand locally as Diamonds well as internationally. Well-known examples are kornerupine, tugtupite, exploration data gathered to date. This lazurite and amazonite. Several multi- Exploration compilation is the common knowledge base coloured rock types have been pro- Diamonds are well-known from the 600 Ma for diamond exploration in West Green- duced on a small scale locally for many old North Atlantic province of carbonatites land. The compilation (on DVD) contains: years and have gained high popularity and ultramafic alkaline magmatism in • 164 scanned reports in Adobe PDF among tourists and collectors, with southern West Greenland, which has been documents from company reports sub- the famous nuummite, greenlandite a target for commercial exploration since mitted to the Bureau of Minerals and and ‘ice blue’ chalcedony being the the mid-1990s. So far this has resulted in Petroleum. There are approximately 96 most favoured. numerous finds of ultramafic lamprophyre 150 mineral analyses from 15 295 and kimberlite dykes and micro/macro dia- samples of till or stream sediment cov- A number of additional classical coloured monds have been recovered from many of ering 4563 localities. gemstones such as beryl, cordierite, peri- these rocks. All work by active companies • 2780 mineral analyses representing 31 dote, tourmaline, garnet, spinel and topaz is still at the exploration stage. kimberlitic rock samples. are known from scattered occurrences, On 24 October 2006 Hudson Resources • 560 classification diagrams on which but their potential has never been tested. Inc. announced the diamond results of the analysed kimberlite indicator mineral The variety in the Greenland geological 2006 exploration drill core program. The grains have been classified and plotted. environment, not least the pegmatite highlight was the recovery of 35 diamonds, All mineral chemistry data have been occurrence, is definite justification for more including the largest diamond ever found examined. systematic exploration for such stones. in Greenland. A sample of a 14.6 kg core • All available geophysical maps. These sample taken from a 4.5 m kimberlite have been scanned in large format, and intercept in the Garnet Lake dyke in the are presented in Adobe PDF documents. Sarfartoq area yielded the largest stone • Approx. 2700 observations of kimber- weighing 0.122 carats. litic rocks. The Geological Survey of Denmark and • Topographic data at 1:100 000 scale Colourless and pinkish diamonds from Greenland (GEUS) recently published a for the regions of diamond exploration Garnet Lake. new digital compilation of all the diamond as at 2004. 2 GEMSTONES OF GREENLAND GEOLOGY AND ORE 7 / 2007 The Majuagaa kimberlite dyke in the Maniitsoq area. (+0.85mm) totalling 0.31 carats or a nomi- exposures known in Greenland was found Potential nal 0.87 carats/tonne. Similarly, the drilling in a steep gully above a stream with The Greenland diamond potential is con- results confirm the Garnet Lake dyke as numerous large boulders of kimberlite. centrated in swarms of ultramafic dykes in being a significantly diamondiferous body, Most of the dyke systems in the Maniitsoq the Sisimiut–Sarfartoq–Maniitsoq region in which can be followed over a strike length area are expected to be archetypical kim- southern West Greenland. Fieldwork in of 900 m, with 450 m down-dip. berlites. 2006 resulted in the recognition of much Many of the kimberlite localities in the larger kimberlite dyke systems in the Maniitsoq area contain abundant dia- Maniitsoq area than had previously been mond-favourable peridotitic and eclogitic Quality reported. The Majuagaa dyke in this area garnets, along with diamond-favourable Quality evaluation of the huge amount is a diamond-bearing and phlogopite-poor chromites and clinopyroxenes. Mineral (more than 1000) of micro and macro dia- ultramafic dyke, which is considered an chemistry data for these occurrences, monds recovered to date from Greenland archetypical kimberlite. The number and along with several occurrences in the is scarce. However, the quality of the dia- size of finds combined with the knowl- Sarfartoq area, became available only monds recovered from the Garnet Lake edge of existence of true kimberlites sup- recently, and it is now possible to address area at Sarfartoq has undergone prelimi- ports expectations of a reasonable poten- the provenance of the indicator minerals nary evaluation by the Hudson Resources tial for diamonds in the province. from till and stream sediment. company. The recovered stones typically In the Sarfartoq area the 2006 results In the field area just east of Maniitsoq, have good colour (colourless to pink) and illustrate the highly diamondiferous nature around the mountain Sillissannguit, new shape (octahedron). The pink diamonds and coarse diamond distribution of the dykes with a combined length of more are always of interest to the gem industry, kimberlite dyke at Garnet Lake in the than 10 km were found in 2006, and in as noted by the company at the presenta- Sarfartoq area. To date, a total of 357kg another area, Timitta Tasersua East near tion. of kimberlite from the Garnet Lake dyke the coast, a system of what is believed to has yielded nine commercial-sized stones be one of the largest kimberlite dyke 3 GEMSTONES OF GREENLAND 520000 mE 540000 mE 560000 mE GREENLAND Greenland Qaqat Aqulerit Qaqqatsiaq Tuk Pikiniq Ivnaarssuunguaq GEOLOGY AND ORE 7 / 2007 Bjornesund Sungasa Nuat Lichtenfels Ruby Island (Tasiusarsuaq) Kaadaaq Northwest Annertusoq Upper Annertusoq East Extension Tasiusarsuaq Waterline Tassiusa Gate Upper Annertusoq Mikisoq Lower Annertusoq Ridgetop Sarfaq Rejane's Occurrence True North Gems Kigutilik Aappaluttoq Kangarssuk Fiskenaesset Project Siggartartulik Date:28/11/2006 Surface Plan Pupiq Puilassut Qavat Author: B. Weston RUBY OCCURRENCES Altiplano 001 Laks Elv Qororssuaq Office: Vancouver Nugussup Qavat Drawing: Scale: 1:200000 Projection: UTM Zone 22, Northern Hemisphere (WGS 84) 024 8 kilometres Map of ruby occurrences in the Fiskenæsset area. Courtesy: True North. Rubies and pink sapphires discovered. However, only limited further collected from each of the two sites. Much Exploration work was done within the concession and of the sampling was carried out by dia- The first rubies were discovered in the West the activity ceased after a couple of years. mond-tipped chain saws and samples Greenland region of Fiskenæsset/Qeqer- In 2004 True North Gems Inc. obtained were flown to Fiskenæsset, where a small tarsuatsiaat in 1966 on a small island, sub- an exclusive exploration licence of a 3600 processing plant was established. The rocks sequently named Ruby Island. In the late km2 area and commenced prospecting in were gently crushed and the heavy miner- 1970s and early 1980s Greenland rubies the area. In 2005 True North collected 3 als were separated. The ruby concentrates caught commercial interest. Prospecting of tonnes of mini bulk samples at five differ- were hand-picked for the largest, best ruby-bearing zones, mapping and bulk ent localities. The ruby ore was processed quality rubies. sampling was carried out by the Canadian at various laboratories in Canada, the UK Prospecting of the area surrounding exploration company Platinomino A/S. and Germany. The rubies were sorted into Aappaluttoq led to the discovery of a band Shortly after the turn of the century the three quality classes: gem (transparent and of multiple ruby-bearing horizons, extend- Greenland rubies captured renewed com- semitransparent), near-gem (translucent and ing for 2 km from the historic locality of mercial interest from Brereton Engineering semi-translucent) and non-gem (opaque). Ruby Island to Aappaluttoq. This region & Developments Ltd. with True North Another ruby showing at Aappaluttoq will be the focus of planned diamond Gems Inc. as operator. yielded 533 grams of gem including a 20- drilling in the future. Detailed exploration for rubies was gram single stone, all derived from a 100- conducted by Platinomino A/S in the 1980s. kilo outcrop sample. Detailed mapping of the Siggartartulik In 2006 True North concentrated their Geological environment zone was made and prospective zones in efforts on the two most promising ruby The Fiskenæsset region is dominated by that area were scrutinised. As a result of localities discovered to date: Aappaluttoq extensive gneiss tracts with enclaves of this, several new ruby-bearing zones were and Kigutilik. A 30-tonne bulk sample was greenstone belts. A large, layered anortho- 4 GEMSTONES OF GREENLAND 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 from Aappaluttoq. From left to right, stones weigh 0.43, 0.42, 0.77, 0.43, and 0.22 rubies.
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