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General Overview     Technical Report     Principal Technical Consultants

Resources/Reserves     Environmental     Show Complete Report
Location:
The Rosia Montana Project is located within the Golden Quadrilateral which is situated within the Apuseni and Metaliferi Mountains of Transylvania, Romania and covers an area of approximately 900 square kilometres immediately to the north of the city of Deva.

location map

Concession Size:
23.8 square kilometres

Geology and History:
  • Dacite Intrusives
  • Epithermal gold-silver mineralization
  • Mining for high grade veins dates back 2000 years
  • 150 Km of grid pattern exploration development
  • Extensively explored over a vertical distance of 400m

Major Targets:
Gabriel's Work Program to Date:
  • Basic Engineering Study completed
  • Optimized Plant Capacity Study completed
  • Definitive Feasibility Study completed
  • Pre-feasibility study completed
  • Scoping Study completed
  • Environmental Impact Assessment (EIA) & Annex to EIA completed
  • Resettlement and Relocation Action Plan (RRAP) completed
  • Annex to Resettlement and Relocation Action Plan completed
  • Update to Zonal Urbanism Plan - Rosia Montana Industrial Area completed

The Rosia Montana Project (the "Project" ) is situated in west-central Romania near the village of Rosia Montana in Alba County within the Rosia Montana mining district. It is located immediately northeast of the town of Abrud, approximately 45 km northwest of the regional capital of Alba Iulia, and 60 km north-northeast of the city of Deva. The village of Rosia Montana and the nearby town of Abrud are the two main centres housing staff and associated infrastructure for the project. The proposed mine and mill site are located at the head of a small drainage basin within steep hilly/mountainous terrain at an elevation of approximately 850 metres above sea level (masl). The proposed tailings management area is located in the immediately adjacent valley to the mine/mill complex. The valley elevation in the area below the site is at approximately 600 masl. As a result of historical mining activities, abandoned waste dumps and tailings ponds exist on the Rosia Montana property. In addition, approximately 140 km of historical underground workings, some dating from Roman times, have been identified within the mineralized zones. Acid mine drainage continues to be produced from the historical openings and dumps. This drainage currently discharges, untreated, into local streams. Gabriel proposes to treat these effluents, as part of its normal operating procedures.

Numerous epithermal gold-silver, porphyry copper and polymetallic ore deposits are located in the Golden Quadrilateral area and have been mined since ancient times. They are of Neogene Age and are situated on the three volcanic NW-SE oriented alignments as follows:

  • Brad - Sacaramb,
  • Zlatna - Almasul Mare,
  • Rosia Montana - Bucium.

The Rosia Montana deposit has been mined since Roman occupation. There have been four principal mining periods:
  • Roman conquest period (106 - end of the Third century)
  • Austrian -Hungarian Empire conquest (from the end of the 17th century until 1918)
  • The period between the Two World Wars (1918 - 1939)
  • Modern Age (1959 up to present).

The Romans mined out the gold rich veins using trapezoidal galleries which followed the vein direction. During Austro--Hungarian Empire times mining operations were developed both in Carnic and Cetate along the more highly mineralized veins (and the zones where veins intersected) using underground methods and developing underground mine workings or stopes, locally called "coranda". During this period accessible ore became deplenished and to ensure that the mining continued and the community stayed in the area the then Emporer funded the construction of the Cross Gallery (714mRL drive) to enable access for the miners to ore in the lower parts of the deposit. Between the two World Wars there were many concession contracts, called "cuxe", awarded to local people which permitted the mining of gold for a defined period of time resulting in many of the rich gold veins being mined out. The employment of children at the mine was a common practice to access the very narrow veins. The ore was transported by foot to water powered stamp batteries from which the gold and other sulphides (including pyrite, sphalerite and galena) contained in the veins were collected. The rivers and streams from the area resulting from the mining and acid mine drainage were so polluted and ran so red that the town was known as "Verespatak" in Hungarian, or "Red River". Gold was then extracted using amalgom (mercury) which was burnt off to recover the bullion (gold and silver). The resulting historical mining methods have left Rosia Montana with a lasting environmental legacy with high levels of mercury in the lakes and water ways and high levels of metals including zinc, lead and related cadmium in the soils and water ways. More recently due to more efficient modern mining methods the lower grade disseminated style mineralization within the bulk of the rock, mining operations were initially developed underground using underground stope and pillar bulk mining methods and later on, as the average gold content of the remaining rock decreased further, ore was recovered using open pit methods and then gold was recovered along with other sulphides in a flotation plant situated at Gura Rosiei. The resulting flotation concentrate was then trucked to Baia de Aries only 15 km away and gold and silver were recovered using conventional cyanide leaching techniques. Open pit mining commenced in 1975 and the state mining company, Minvest, ceased underground operations in 1985, but continued to operate a state subsidized open pit mining operation. This open pit mine is expected to cease operations in the second half of 2006.

The Rosia Montana deposit is hosted in a maar- diatreme complex intruding Cretaceous age fine grained sediments predominantly comprised of black shales, with subordinate sandstones and conglomerates. The main lithology types found within this complex consist of phreato -- magmatic breccias, reworked breccias, and re-worked lake sediments, intruded by sub-volcanic dacite bodies. These main dacite bodies are the Neogene gold-silver bearing intrusions known as the "Cetate Dacite" and "Carnic Dacite". Many phreato-magmatic and smaller phreatic breccias which display varying degrees of mineralization, have been identified and mapped within the maar-diatreme complex and within the dacite bodies. The phreato-magmatic breccias contain clasts of Cretaceous black shale, sandstone and conglomerate, and crystalline basement clasts such as gneisses and schists in addition to dacite clasts. One of the largest, the "black breccia" or "glamm" forms a sub-vertical breccia pipe at the very heart of this complex, being situated between the two dacite intrusions does not contain significant mineralization. Another the "Corna" breccia situated to the south of Cetate and Cirnicel has been emplaced post-mineralization and contains primary magnetite and altered dacite clasts but no significant mineralization.

Between Tarina and Jig a series of polymict diatreme breccia bodies have been identified which have intercepted and re-worked the vent breccia. These breccias are the product of deep phreato -- magmatic eruptions along structures, which also explains their cylinder or elongated shapes. In general, these breccia are mineralized. In the Igre zone, dacite and polymict breccias are found within host Creatceous sedimentary units and are interpreted as branches of the diatreme breccia emplaced along smaller faults. Extrusive andesites are found at the northern and eastern side of the project area and they formed a thin to medium thickness blanket overlying the maar complex. Within this succession, the lower levels are represented by pyroclastic flows and volcanic ashes while to the north and east, the lava flows are seen covering the pyroclastics. These volcanics occurred after mineralization at Rosia Montana.

The Rosia Montana deposits are epithermal, low to intermediate sulphidation systems with relatively simple metallurgy. The mineralization does not contain deleterious antimony, mercury, arsenic or tellurium. Gold occurs as electrum (gold-silver), associated with sulphides (predominantly pyrite) and in the native form. Mineralization is associated with quartz-adularia alteration and later carbonate-clay-sulphides and occurs as disseminations throughout the host rocks. The bulk of the known reserves are localized within the two adjacent dacitic bodies, Cetate (in the west) and Cirnic (in the east). The surrounding breccia units host the Orlea, Cirnicel and Igre deposits and much of the breccia hosted mineralization remains untested.

Cetate
The Cetate deposit is hosted in the western most of two main dacite dome complexes located at Rosia Montana. Peripheral and internal phreato-magmatic breccias comprised of dominantly dacite clasts grading out into mixed volcanoclastic breccias and vent breccia surround the main dacite body. Mineralization occurs as disseminations within the dacite and breccias as well as in later carbonate-quartz-clay-sulphide veins. Veins and fractures are orientated NNE-SSW to NNW-SSW and veining is volumetrically small. Mineralization is situated within a dominantly north to northeasterly trending zone and appears to plunge and is open to the south and at depth, notably in the Gauri zone. An open pit mining operation is currently being conducted over the Cetate zone by Minvest but is expected to cease operation in the second half of 2006. The main zone of mineralization extends along a strike length of approximately 800 metres and is up to 500 metres wide.

Cirnic
The Cirnic Dacitic dome complex is "mushroom shaped" in cross section and at depth forms a sub vertical intrusive plug with an approximate circular cross - section. The dacitic dome occurs as the eastern most dome. Extensive gold-silver mineralization has been defined and occurs in two main zones. The largest is within a NE-SW corridor along the western margin of the Cirnic dacitic and the second within a roughly E-W trending zone on the southern margins of Cirnic. Away from the main zones of pervasive mineralization and silicification, alteration grades into argillic alteration.

Precious metal mineralization occurs as disseminations associated with pervasive quartz-adularia-trace pyrite alteration overprinted by carbonate-quartz-clay-trace sulphide veining. Early weakly mineralized black siliceous veins (chinga) also occur and the Cirnic has been cut by internal mineralized phreato-magmatic and phreatic breccias.

The Cirnic deposit was subject to the greatest degree of underground development of the five mineralized areas at Rosia Montana. Thirteen levels of previous adits from the 1960's to 1980's as well as underground workings from the 18th and 19th centuries provide access into the interior of the hill.

Cirnicel
The Cirnicel deposit is located about 400 metres to the south of Cirnic and is hosted in volcaniclastic maar-diatreme re-worked sediments composing multi-clast breccias and tuffaceous grits, and to a lesser extent mixed breccia hosting dominantly dacite clasts. The area is intensely altered with strong silification at the core with surrounding QIP and argillic alteration. Disseminated gold-silver mineralization is associated with disseminated sulfides, with lesser sulfide vein stockworks and individual carbonate-quartz-sulphide veins. The Cirnicel zone occurs as a sub-horizontal zone of mineralization.

Jig-Vaidoaia-Igre
At Jig-Vaidoaia, located about 550 meters north of the Cirnic dacite intrusive, dacite outcrops above maar-diatreme sediments and volcanoclastics as well as Cretaceous age shales and slates and is expressed as a small hill. The Vaidoaia dacite may represent a remnant of the larger dacite dacte body, the roots of which have not been located to date. Mineralization is considered to be sourced along local structures. The dacite, volcanoclastics, and sediments are brecciated and intensely altered; this alteration includes silification, argillic, and disseminated sulfides. The small dacite body at Vaidoaia is situated on the intersection of major WNW and NE trending structures. The NE trending structure may have displaced the Cetate and Cirnic bodies.

Gold- silver mineralization is found within the dacite, dacite breccia, vent breccia and within Cretaceous black shales. The mineralization occurs dominantly as disseminations, small veinlets and stockworks and secondarily as quartz sulfide veins that trend both north-south and east-west.

The Igre prospect, located immediately west of Jig-Vaidoaia, is contained within strongly altered (sulfides and silicified) volcaniclastic sediments, phreato-magmatic breccias and local small dacite dykes and dacite breccias. Mineralization has been emplaced and focused along and adjacent to steeply south dipping structures with silicification and veining also forming sub-horizontal zones of mineralization within the breccias and volcaniclastic units with more vertical zones emplaced within the Cretaceous sediments.

The Jig-Vaidoaia-Igre zone appears to have formed within a structurally linked WNW trending zone, which remains open to the ESE. To the east the zone is linked with the relatively untested Cos zone. The Jig-Vaidoaia zone remains open to the NE also.

Orlea-Tarina
Gold-silver mineralization in this area is hosted in a series of sub-parallel quartz sulfide veins hosted in volcaniclastic sediments located to the north of the Cetate dacite intrusive. Mineralization has been located north of Cetate at Carpeni and it appears that mineralization will be continuous to Orlea. Mineralization at Orlea has been emplaced along steeply dipping E-W trending structures and sub-horizontal veins. Pervasive silicification, sulphides, carbonate and clays form sub-horizontal zones which host pervasive precious metal mineralization.
The mineralization at Tarina appears to form the intersection of N-S trending structures from Orlea with the main ENE trending regional structures which have emplaced the Igre deposits. The zones remain relatively untested but are known to host precious metal mineralization within volcaniclastic sediments, phreato-magmatic breccias and local small dacitic dykes and dacite breccias. Mineralization is hosted in carbonate-quartz veins, silicificed zones and zones of sulphides and clay alteration.

The Rosia Montana deposits are surrounded by a spatially extensive zone of intense hydrothermal alteration (dominantly QIP, argillic and quartz-adularia alteration or commonly silicification). The mineralized intrusives and breccia pipes are topographic highs making them ideal for large scale open pit mining with low strip ratio. These deposits collectively represent a major world-class, under-developed resource, arguably the largest in Europe.

Between 1997 and 2005, the Company carried out and completed a large geological exploration program consisting of surface mapping and sampling, underground sampling and mapping of the existing galleries, as well as surface and underground drilling, geo-physical surveying and measurements, and topographic surveys. In addition the Company conducted geochemical, mineralogical, and petrographic analysis and studies in addition to other specific exploration activities. This program defined four main mineralized zones: Cetate, Carnic, Orlea and Tarina-Igre-Jig-Vaidoaia. The gold content is generally relatively low (average 1.3 g/t Au), and disseminated throughout the whole rock mass. Based on the exploration program a total measured and indicated resource of 350,000,000 tonnes at a grade of 1.3 g/t of gold and 6 g/t of silver for a contained total of 14,600,000 ounces of gold and 64,900,000 ounces of silver in addition to an inferred resource of 30,000,000 tonnes at a grade of 1.2 g/t of gold and 3 g/t of silver for 1,200,000 ounces of gold and 3,000,000 ounces of silver. The deposit remains open in several directions and an exploration program has been ongoing.

While the proving of the recoverable reserves is sufficiently complete to allow the development of the new mine, the geological exploration program will continue at a lower level of intensity in order to identify new mineralized zones and increase the knowledge and understanding of the already calculated resources.