Oberzeiring Polymetallic Project in Detail
General Project Information
Austria is a very mining-friendly country. The Austrian governments plan for mineral resources even served as a blueprint for a notice of the EU to its member states: “In the EU the regulatory framework has to be structured in such a way as to encourage a supply with mineral resources from European sources.”
The Styrian Alps was once famous for their abundance in gold and silver occurences. A 150 km limestone ridge, which was covered with slate, carrying ores of gold, silver, antimony, lead, zinc, copper and iron.
This stretched from the western border of the Poels valley onto the Mur river to Möderbrugg and possibly further beyond.
Our license area is situated in the mineral-rich Austrian province of Styria, about 120 km to the south-east of Salzburg and about 85 km to the north-west of Graz. It covers the south-eastern slopes of the Woelzer Tauern, west of the large Pölstal fault zone and comprises 99 granted claims near the town of Oberzeiring.
This area has a well known history of mining – mainly for gold, silver, copper, lead and iron – as far back as to the early Middle Ages. Historical artifacts even date back to the Bronze Age, to the Illyrians, the Celts and the Romans.
Nowadays the exploration of ancient mining areas with modern methods is common practice worldwide in discovering as yet unknown mineralization/ore bodies.
Oberzeiring Polymetallic Project
Our project with 99 licensed claims near the town of Oberzeiring comprises an area of about 35 square kilometers and is situated between 850 and 1,250 m above sea level. The region around Oberzeiring has excellent infrastructure. The local railway station is only a few kilometers away and the remote areas of the project are within easy reach by forestry roads.
Richmond’s management has already established very good contacts with local authorities and landowners, who both welcome our exploration work and possible reopening of mining activities. Locally the lack of job opportunities in the region is a strong motivating factor for our proposed development work.
History of the Silver Mines of Oberzeiring
By reviewing early findings and local history one can trace silver mining in the upper Pöls valley back to 1000 B.C. Oberzeiring in ancient times was one of the largest silver mines of the eastern alps, has for the first time been documented 1265 and been granted the status of a market town in 1279. In this 13th century it was in the possession of all the rights of a mining town and until 1663 also the seat of the mining court. Of particular significance had been the granting of the minting right in order to coin the “Zeyringer Pfennig”.
The “Mines at Zeiring” were famous for their abundance of silver until the late Middle Ages, during which King Rudolf of Habsburg conquered the district of Styria in order to possess these rich deposits.
At that time ten silver smelters had been processing silver-rich mixed ores and high-silver-containing lead ores, some ores even showed locally high gold grades. Through the high profits from mining these deposits, the contstruction of many buildings in Vienna, the capital of Austria, got financed and Zeiring got the honorary name of “Mother of Vienna”.
In the year 1361 mining ended abruptly due to a sudden and unexpected flooding event at a depth of about 60 meters underground. This flooding event caused 1,400 miners to drown according to the chronicles. Evidence of this tragic accident is documented in several hitsrical records and also depicted in a medieval mural in the hall of the Maximilian castle Hahnfelden in Unterzeiring. The event is also documented in the inscription of a map of Noricum, which is availabe in the regional library of Graz.
In every century thereafter futile trials to dewater the flooded mine workings failed due to lack of adequate technology.
Just a few hundred meters from the mine entrance, Emperor Maximilian I. had built the aforementioned castle of Hahnfelden, where he is said to have resided for three months around the year 1475 and also 1506, to personally supervise dewatering and reactivation operations for gold & silver mining. Later the abbey of Admont, many private entrepreneurs, and a state commission on mining under direction of Empress Maria Theresa had tried a reopening, but without electricity and machines this could not be achieved. Small scale mining took place up until the end of the 18th century. Around 1816 the mining of larger quantities of silver containing galena is noted in historical documents. In the year 1840 the mining of silver had been followed by that of iron ore, which ended 1886.
The 20th century in Europe was affected by two world wars and all kinds of political upheavels which did not induce mining and exploration entrepreneurs to follow up on the findings of centuries ago. However, in the late 1950s and early 1960s barite was mined for some years due to a property of barite blocking radiation, obviously a reaction to a fear of an escalation of the cold war.
Are there still Silver Deposits around?
A state consortium on mining called by Empress Maria Theresa answered this question as being probable. Considerable manual effort was put into the construction of an exploration decline (aka a tunnel) about 6 km away from the Mur valley in the direction of the Unter- and Oberzeiring silver mines. This plan to build such a tunnel of several kilometers by pure manual labour spotlight’s the importance of the continued development of this silver deposit. Work on the tunnel came to an end due to the outbreak of the “Erbfolgekrieg” (war on succession) of seven years, with all men able to serve being subscripted. Consequently war debts and the lack of financing thwarted the continued development of this project. These repeated trials to dewater the ancient mines are a clear indicator to the historical belief that much silver mineralization had to be disocvered near the mines.
Regarding the flooding event, the known mine historian Professor Franz Kirnbauer writes in his paper of 1971: “It is beyond doubt, that at the time of this mining accident the miners faced excellent ore, otherwise so many smelters would not have been operating.”
The scientific papers in the mining libraries and unpublished results report on the locally astonishingly high grade of silver in the deposits of Zeiring. In the area of Unterzeiring – Oberzeiring – Möderbrugg, the old and partly decayed system of tunnels are said to have had a total length of more than 25 km and are built by hand! The silver deposit of Oberzeiring is a carbonate replacement type deposit which appears to have been “preserved” since flooding and with appropriate capital and employment of modern technology it may be possoble to reactivate. Electrical energy and the use of remote mining machines, water pumps, ventilation systems and ecological treatments are routinely used in modern mining operations today.
High Grade Gold with Silver in The Oberzeiring Deposits
As quite often observed in the Eastern Alps also the silver of the Oberzeiring deposit is a natural alloy of gold and silver (“electrum”). Analysis of silver mineralization from “Ostfeld” show a gold to silver ratio of 1:10 to 1:200, meaning that the silver from Oberzeiring may contain up to 10% gold. Samples of silver mineralization without gold contents is also observed, resulting from the different processes in silver mineralization deposition.
Historical sampling of artisanal mine waste dumps (“old mines”) were analyzed providing indications of high potential grades. Previous analysis by the Technical University of Vienna yielded grades of 930 g/t, 850 g/t, 1,250 g/t, and 1,070 g/t silver in galena, collected at the “West field” in Oberzeiring. A sample from Piergrube (Middle field) returned silver in galena of 832 g/t and 956 g/t in the “Fahlerz”, both with 5 g/t gold. A sample of galena analyzed in the year 1961 by “Scheideanstalt Wien” (affineur) from “Klingerbau” returned 315.5 g/t silver and 2.5 g/t gold. The former mining entrepreneur Dipl. Ing. R. Hirn in connection with the mining of barite reported a sample from the “Ostfeld” in Oberzeiring of 114 g/t gold and 1,106 g/t silver, as well as a sample of markasite taken in “Klingerbau/Gamsbergzeche” yielding 80 g/t gold, both analysis done by affineur ÖGUSSA in the year 1963. According to geologist Dr. Neubauer samples of iron ore contained 5 g/t gold. Silver samples from the dump at “Erbstollen” displayed a yellowish colour when viewed under ore microscope, likely due to their content of gold. Ludwig Apfelbeck (1920) quotes from an old report from the Middle Ages on the mining of gold-bearing copper ore: “… considerable amounts of gold had been handed in to the imperial encashing office in Graz”.
An analysis of a “Zeiringer Pfennig” done by X-ray spectrometry in the year 2012 yielded an assay of gold of more than 15,000 ppm.
According to old reports the samples of galena from Zeiring were said to contain up to 4,000 g/t silver. In last mineralisation event rich silver-antimony mineralisation with pure silver were formed. in the Zeiring deposits. According to mine historian Professor Franz Kirnbauer, at that time raw ore with a reported 10 % silver content – one hundred kilograms per ton – had been found locally.
Many Ancient Artisanal Gold & Silver Mines South of Oberzeiring
In the area near Unterzeiring/Katzling there are more than fifty ancient silver mines along a strech of about 5 km. These deposits often have only been mined close to the surface, due to locally high-water table conditions thus thrawting the exploration of potential deeper extensions to these bodies (Au/Ag and Ag-Zn-Cu). Also, possible zinc deposits may also exist given that zinc was not mined nor explored for in the ancient times. In the “Matthisabaue” south of Oberzeiring it is said that iron ore with 1,200 g/t silver and high grade of gold had been found, as well as copper mineralization with gold. In spite of the large area with silver deposits near Unterzeiring/Katzling, there has been no metalurgical analysis of historical ores. The only reports are published by P. Walser (1974) about the strong to very strong silver anomalies in mine dumps.
Newly Discovered Occurrences
In the process of formation of the Alps the Pöls valley had obviously been displaced to the northwest. The deep fault zone caused by this favoured the repeated inflow of ore solutions and resulted in a high density of deposits. In the area around Pichl (Unterzeiring/Katzling) there are anomalies outside the old system of tunnels with partially strongly elevated silver- and non-ferrous metals values in the ground and in rock samples. The locally high Ag/Sb values remind of the nearby tunnels in Oberzeiring with pyrargyrite (associated with pure silver). A historical soil sample contained about 4% Zn with 1,456 ppm Ag and a second one 2.4 % Pb with 2,424 ppm Ag – these are high values in soil samples. Mineralization, which causes the very high silver grades in the soil samples, could be encountered at shallow depths and should descend abruptly down to a great depth. The paragenesis Ag-As-Sb is an indication of a possible, local gold leadership in the deeper underground. In addition, Silbermine Zeiring GmbH has executed a programme of geochemical sampling in 2013. Of 27 samples of mixed rock, 4 samples showed up to 4.2 g/t Au and 8 of it interesting contents of silver.
The samples had been taken along a 4 km strech of the Pöls valley fault zone south of the village of Oberzeiring. The rock mixed samples with the high gold content from old tunnels or mining dumps come from two different zones, which are spatially separated by about 3 km. One can expect, that along the large Pöls valley fault zone, hidden and unknown gold/silver ore mineralization may be found.
In the course of geophysical measurements by Silbermine Zeiring GmbH (2000+2004/2005) some strong anomalies in the area of the old silver mines near Mauterndorf, Pichl, Klumgraben and Dorfgraben have been detected, waiting for further examination.
Publications by Experts
The considerable richness in precious and other metal deposits repeatedly lead experts to conduct extensive research. Some of the results have been published and are available at specialized libraries on geology and mining. The large Pöls valley fault zone with its multiple network systems of fractures formed ideal paths for hydrothermal activity. Prof Dr. K. Metz wrote in the year 1977: “The system of fracture spermeates the Wölzer Tauern and produces a complete fracturing of the limestone marbles.”
In the year 1974 Dipl- Ing. Dr. mont. Peter Walser reports on the ore deposits in the mountain area near Unterzeiring: “To the south of Katzling and east of Klum-Hube there is the mining area D….With the exeption of mine V all other mines show strong anomalies regarding silver, lead and zinc….the mine VI has large dumps and above all very high silver anomalies in the whole area. It is astonishing that in the literature these mines that possibly once contributed considerably to the production of silver in the area are not mentioned.” 1967 DDr. J.G. Haditsch writes about the mine dumps at the eastern border of Oberzeiring: “… the rock thin sections, I have seen, confirm this … and make it probable, that the well known high silver grades of the ores of Zeiring … was more due to the rich pyrargyrite (and pure silver) content…”.
Furthermore, Haditsch mentions the bournonite mineralization as an important carrier of silver and gold as well as generations of lead-, zinc- and copper mineralization events … ascending as well as descending silver shows a strong reflexion and – say against white bleiglanz – a marked yellowish tint. Since the specs did not get darker with time or prolonged irradiation under a microscope, it can not be pure silver, but an alloy with gold (electrum). (Monograph of the Ore Deposits of Zeiring, by author DDr. J.G. Haditsch)
Dr. Walter Neubauer speaks of Oberzeiring as a deposit characterized by antimony and with a steep root. Furthermore, Neubauer writes: “According to old reports the grade of silver in the galena has been locally up to 4,000 g/t … and mentions a spectographic analysis of sphalerite yielding germanium 50 g/t, gallium 300 g/t and indium 10 g/t. “
(For more information please see technical NI 43-101 report available for download an our webpage and on www.sedar.com)
Planning of Exploration
Based on the promising results of the past we plan a multiphase modern exploration program moving forward:
- Geochemical areal soil survey, additional mapping of unknown mine dumps and sampling of all existing mine dumps
- geophysical surveying including structural analysis
- delineation of drilling targets with follow up core drilling
- reporting estimates of the size and the extent of mineralization
A multi-step drilling program this is planned. Compilation of data obtained from drilling numerous shallow holes in near-surface rock, together with the geophysical surveying results, structural analysis and geochemical sampling at the surface, will serve as a basis for planning of deep drillholes into identified targets. Furthermore restoration of the approximately 600 m long “Johannes Erbstollen” will be undertaken to allow access to flood part of the 1361 mine workings. This will enable underground sampling, geophysics and drilling. Systematic testing of the deep ancient mining sites will be also possible after mine dewatering. Each of these planned steps means a continuous approach to the potential definition of a commercially project and a concomitant increase in Richmond’s share value.
The following precious metals, industrial metals and critical raw materials are thought to occur with mineralization of the project area and could be mined as by-products in addition to the “green” marked main products, which would enhance the economic viablility of any potential future mining activities at the Project:
Oberzeiring: Ag, Au, Sb, Cu, Zn, Pb, Barite, as well as Ga, Ge and In
The latest table of critical raw materials for the EU of September 29, 2017 now contains 27 critical raw materials (after 14 critical raw materials in 2011 and 20 critical raw materials in 2014):
Antimony, Barite*, Beryllium, Bismuth*, Borate, Cobalt, Coking coal, Fluorite, Gallium, Germanium, Hafnium*, Helium*, Indium, Magnesium, natural Graphite, natural Rubber, Niob, Rock Phosphate, Phosphorus*, Scandium*, metallic Silicium, Tantalum*, Tungsten, Vanadium*, Platinum Group Metals, Heavy Rare Earths, Light Rare Earths.
(The raw materials underlinded and marked with * are new in the list as compared to 2014.)
Antimony (Sb), Gallium (Ga), Germanium (Ge) Indium (In) and in particular Barite are defined by the EU as “critical raw materials” and therefore especially in demand, since there is hardly any occur within the area of the EU. There are subsidies available in the EU of several hundred millions Euro for the detection of such raw materials in connection with the development of innovative exploration methods.