PGE

Metals for the New Millinium

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Over the last 48 months, a previously ignored group of metals has forced its way into the collective consciousness of the world's minerals industry. These metals are referred to as Platinum Group Elements (PGE's) and normally include platinum, palladium, rhodium, ruthenium, osmium and iridium. Of these elements, only platinum and palladium are mined as primary metals. The other four PGEs are recovered as byproducts, primarily from platinum, palladium and/or copper-nickel production. Research conducted by Avalon Development suggests Alaska contains significant potential to host economically attractive PGE occurrences in a wide variety of geologic settings. With few exceptions, there has been virtually no targeted exploration of the nearly 200 known Alaskan PGE occurrences. Extremely favorable current and future PGE supply - demand fundamentals suggest Alaska's prospective PGE potential will come of age in the new millennium.

General Geology of Alaska PGE Deposits

There are five main geologic settings that favor PGE deposition in Alaska. This classification is modified from one recently suggested by Foley and others in Economic Geology Monograph 9 (1997):

Deposit Model 1: Alkaline-to-subalkaline Composite plutons: There are 27 known PGE-bearing alkaline to subalkaline composite plutonic occurrences in Alaska. Composite plutons are the least well documented and least understood of the potential PGE hosts in Alaska. These composite plutonic complexes are highly variable in age and their associated igneous rocks range from granitic to mafic to ultramafic. Alkaline and silica-saturated plutonic rocks are volumetrically more common than mafic to ultramafic intrusives. Many are concentrically zoned, with granitic cores and more alkaline and mafic outer zones. They form above active subduction zones in convergent plate margin tectonic settings and are thought to be the result of interaction between mantle and crustal melts. There is a growing body of evidence that suggests composite plutons and Ural - Alaska plutons are end-members of a range of plutonic complexes whose gross tectonic origins are similar. Zoned plutonic bodies which exhibit alkaline to subalkaline plutonic phases may have been generated under extensional conditions within a back-arc basin setting. Zoned plutonic bodies which are dominated by mafic and ultramafic rocks (Ural - Alaska) have chemical and physical characteristics suggestive of derivation within compressive regimes above active subduction zones. A number of the Alaskan composite plutons are associated with substantial placer gold deposits which contain PGEs in minor amounts in heavy mineral concentrates. Composite plutonic complexes also have potential for precious metal, base metal, uranium, tin-tantalum-niobium and rare earth deposits.

Deposit Model 2: Differentiated sill-form complexes: There are 31 known PGE-bearing differentiated sill-form type occurrences in Alaska. The best known Alaskan sill-form complexes are of Late Triassic age and are interpreted to be comagmatic feeders to the extensive Nikolai basalts of the Wrangellia terrane of southcentral Alaska. This belt of rocks extends into the western Yukon where it hosts the past producing Wellgreen copper - nickel - PGE deposit. These complexes consist of ultramafic and lessor mafic rocks with associated PGE mineralization in placer deposits as well as lode deposits associated with copper - nickel sulfide mineralization. Recent exploration in the central Alaska Range has identified a number of untested prospects containing anomalous PGEs. A number of these prospects were known to contain copper and nickel mineralization but were not evaluated for their PGE content until recently.

Deposit Model 3: Synorogenic Layered complexes: There are 10 known PGE-bearing synorogenic layered occurrences in Alaska. The bulk of the world's platinum production is derived from synorogenic mafic intrusive layered complexes, primarily the Bushveld and Stillwater complexes. Sulfide and/or chromite and/or PGE minerals accumulate in distinct layers which form under quiescent conditions within a large magma chamber. In Alaska, all known layered complexes are Tertiary in age and are composed primarily of gabbro and norite with lesser gabbronorite, troctolite and anorthosite. Alaska deposits are hosted within the allochthonous Chugach Terrane in northern southeast Alaska. These prospects are essentially copper-nickel sulfide deposits with secondary amounts of PGEs. For example, the Brady Glacier deposit resources contain 100 million tons grading 0.5% nickel and 0.3% copper with 171 parts per billion total PGEs (approx. 0.005 oz/ton).

Deposit Model 4: Ophiolitic complexes: There are 63 known PGE-bearing ophiolite type occurrences in Alaska. Ophiolitic complexes originate at ocean ridge spreading centers and are commonly composed of a basal unit consisting of differentiated ultramafic and mafic rocks overlain by sheeted mafic dikes which are in turn overlain by submarine basaltic lava flows often associated with deep-water marine cherts. Ophiolites are typically more complex structurally than other PGE-permissive settings due to transport on the host oceanic plate and their subsequent obduction at convergent plate margins. Jurassic age ophiolites are common throughout Alaska's major mountain belts but the distribution of PGEs in them is poorly documented. Ophiolites commonly contain anomalous chromium, copper and nickel but the distribution of PGEs in Alaskan ophiolites is poorly documented.

Deposit Model 5: Ural-Alaska type complexes: There are 35 known PGE-bearing Ural - Alaska type occurrences in Alaska. Ural-Alaska type complexes are mafic to ultramafic plutonic bodies that commonly are associated with basal portions of Mesozoic volcanic arc terranes. These complexes commonly are associated with linear orogenic belts which range in length up to 1,000 kilometers. Ural-Alaska type complexes normally are concentrically zoned, with dunite or peridotite cores surrounded by pyroxene-bearing rocks (pyroxenite, websterite and lherzolite) which are in turn rimmed by more differentiated rocks including gabbro and norite. Ural-Alaska complexes commonly range in size from 1 to 10 miles in diameter and cause variable sized contact metamorphic aureoles in surrounding country rocks. The world's first platinum producers were the Choco placers derived from Ural - Alaska type complexes in Columbia however these types of complexes are best known from their type localities in the Ural Mountains of west-central Russia and from southwestern and southeastern Alaska and northwestern British Columbia. Several of these complexes, including the Goodnews Bay complex in southwestern Alaska and the Kondeur deposits in the Urals, have been deeply eroded resulting in formation of significant placer PGE deposits. With the exception of the Salt Chuck and Goodnews Bay prospects, little recent exploration has been directed toward PGE mineralization in Ural - Alaska type complexes in Alaska.

Deposit Model 1: Unclassified type complexes: Any other model type not previously mentioned.

DESTINATION 2008 - ALEXANDER PLATINUM BELT

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One of the most important and often overlooked details regarding PGEs in Alaska is that 100% of its historic palladium production and over 99% of its historic platinum production has been derived from one type of geologic setting, the Ural - Alaska type mafic/ultramafic complexes. Ural - Alaska type complexes were recognized as a distinct geologic entity in the early 1900's in both the Ural Mountains of central Russia and in Alaska and northwestern British Columbia. However, these complexes were the world's first and only sources of platinum until the 1920s. It was about this time the Russian, Canadian and American geologists began to realize that most of world's platinum had been derived from geologic settings which were remarkably similar in composition, size, geometry and other geologic characteristics. One such belt, the Alexander Platinum Belt, stretches for over 350 miles though southeast Alaska and hosts at least 11 Ural - Alaska type complexes. Only one of these occurrences has had past PGE production and only one other occurrence was explored specifically for its PGE potential in 2000. Both returned extremely promising PGE results from 2000 field programs. The Alexander Platinum Belt represents one of the least explored metallogenic belts in Alaska and is expected to become an active destination for corporations and individuals conducting PGE exploration in 2002 and beyond.

PGE's for the New Millennium

The future of PGE exploration, development and production seems bright despite the difficult political, social and environmental hurdles which face the mining industry on a global scale. Some of the factors which contribute to this conclusion include:

1. Platinum is still the rarest of the precious metals and retains its historic role as a store of value and as an investment commodity.

2. Both the growing autocatalyst technology sector and several platinum-group mines now in and nearing production are the direct result of government intervention to clean vehicle exhaust emissions. This is a rare instance in which an environmental policy is the cause of expanded mining activity.

3. In contrast with gold and silver, there are no large above-ground platinum stockpiles that can be sold into the market to fill the gap against significant supply shortfalls or disruptions.

4. The only known above-ground palladium stockpiles are in Russia and these are rapidly dwindling as Russia has met annual demand shortfalls over the last 10 years from their above-ground stockpiles.

Alaska PGE Potential

Alaska is well positioned to take advantage of a unique situation in the metals industry. Unlike virtually every other metal, the PGEs are facing a strongly increasing future demand coupled with a dwindling or flat supply. Conditions such as these encourage active exploration for and development of PGE resources. Alaska's diverse geological history has left it well endowed with prospective PGE prospects which have been ignored for most of the last century. With few exceptions, what we know about Alaska PGE occurrences was derived as a secondary benefit of exploration for other metals such as copper, nickel, chromium or gold. Avalon Development has taken the first steps to identify, categorize and prioritize the most promising PGE prospects in Alaska. The first two targets acquired for our clients have returned extremely encouraging results from properties that were previously available for staking and acquisition. We have identified other high priority PGE targets, several of which are currently open to location. Avalon Development's experience and expertise can help you achieve your acquisition goals quietly and efficiently, without you having to invest the time and money to create the database and targeting tools you need to become competitive.

If you are interested in learning more about PGE opportunities in Alaska, contact Avalon Development and request a free copy of the "white paper" Exploration Potential for the Platinum Group Elements in Alaska and let us help you explore for the metals of the new millennium.