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Mark R. Lamb, Torres, Sonora, Mexico (communication to the Secretary*): I have read Mr. Merrill's paper with much interest, and cannot but accept his challenge as regards the cost of the clean-up at the Homestake mill. If I understand him correctly, the two men take the precipitates from the presses in about six hours, and do nothing towards refining them. If that is so, it would correspond to the work four men do here in about eight hours—that is, to clean the box and to place the precipitates in the driers. In order to make a fair comparison, the bullion in each case should be stated in ounces, since it is as diflicult to precipitate silver as gold, and our bullion is mostly silver. Bullion to the value of $50,000 is equivalent to a weight of about 2,500 oz. At our last clean-up eight standard bars, each 1,100 oz. in weight, were made, which equals a total weight of 8,800 oz'. Four men had the precipitates drying by 8 p.m. This plant, the Minas Prietas works of Charles Butters & Co., at Minas Prietas, has square-bottomed electrolytic vats, an arrangement which necessitates the handling of all the precipitates in buckets. The Butters plant at Virginia City, Nev., is equipped with conical vats, and probably could make a still better showing under similar conditions. Another point is that common labor only is required. (Ordinary laborer's wages at Minas Prietas are $0.70 gold.) I may say also that, except for the convenience of the refinery, the box could be cleaned monthly, instead of bi-monthly, at only a slight additional expense. The comparison, if made a few months ago, would have been much more in favor of the electrolytic process, as the tailings handled at that time contained a large quantity of copper, and the amount of zinc-dust required would have been enormous.

Jan 1, 1904

By Ian Vaz, Takefumi Takuma, Rafael Holcombe, Chris DellAringa

"This paper will discuss the successful installation of seawalls for the first phase of a project in Long Beach in California known as the Naples Island Permanent Seawall Repair – Phase 1. How an unconventional method of pile driving resulted in the reduction of the duration of the project while using less space and maintaining minimal noise impacts to accommodate neighbors will also be discussed. Included in the paper will be how non-vibratory equipment used on this project also significantly minimized the risk of disturbances as well as settlement on residential properties; which in turn greatly reduced the risk of damage to existing structures. The first phase of a 6-phase project along a section of the canals with tight clearances and proximity to residents included the installation of a 1,912 linear-foot steel sheet pile wall system in front of the existing deteriorating walls from January until March 2015.INTRODUCTIONThis project was located in the Naples Island neighborhood of Long Beach in southern Los Angeles County, California. After 80 years of the same seawall structures lining the canals of this beautiful neighborhood, the City of Long Beach Department of Public Works decided that it was time to better protect the area’s multi-million dollar homes by repairing its crumbling seawalls. The City realized that the walls will only become worse due in part to several concerns, including bending failure for the already deflecting walls. According to the City, certain sections of the walls had a significant risk of global failure if the area experienced a “moderate” near-source earthquake (City of Long Beach, CA, 2014b). Although the seawalls were in need of major repair, this would not be simple. Due to the tight clearances of the seawalls between the homes and canals, installation would be difficult with heavy, conventional construction equipment.Phase 1 of the project involved installing sheet piles on the water side in front of existing and aging vertical concrete seawalls between the Ravenna and Toledo Bridges along the Rivo Alto Canal. See Figure 1 for the General Plan for Phase 1. Financing for this project by the City’s Tidelands Capital Improvement’s Division allowed the construction to begin in a timely manner. However, the challenges for the City included regulatory restraints that further complicated the construction in terms of the duration of the project due in part to numerous regulations from several regulatory agencies."

Jan 1, 2016

By Norman Lecuyer, Jacque Nantel

"The Chadbourne Project, located within the limits of the town of Noranda, Quebec, will make use of backfill materials to fill the voids left by the mining of stopes and pillars. A series of tests were conducted on different mixtures of slag and pyrrhotite tailings materials to evaluate their properties. The tests are described and some pertinent results are given in the paper.IntroductionThe Chadbourne Project is located in the centre of the Town of Noranda, Quebec, with houses as close as 120 m from the blasting operations. The ore is mined using the vertical crater retreat method. The voids left by mining activities will be filled. A program of pillar recovery will follow.Considering the proximity of houses and the need to recover pillars, the backfill program must be carefully laid out. No subsidence can be tolerated on surface.With these objectives in mind, a test program was undertaken by Nantar Engineering Limited and Queen's University to evaluate the possible ba ckfilling alternatives available to Chadbourne. One of the possibilities retained was the use of a backfill composed of broken slag material from the Horne Smelter and pyrrhotite tailings deposited on the Horne's pond a number of years previously.The back fill used at the Horne Mine until the mine closed in 1975 was composed of a mixture of 97% granulated slag and 3% pyrrhotite tailings. The tests leading to its use underground at the Horne Mine were described by Patton in 1952. The structural properties of the Horne backfill were ""intuitively"" known; it was agreed by all at the Horne Mine that the backfill was behaving remarkably well. Some were labeling it ""the best backfilling material in the world"". Its strength was said to be that of a weak concrete. All of the preceding indicate that the Horne backfill had never had its structural and other properties determined in the laboratory."

Jan 1, 1983

By C. E. Brown, D. C. Helms, O. W. Shimer

The early history and progress of anthracite stripping, from the first known operation at Summit Hill in 1821 through 1917, was covered in 1917 in a paper by J. B. Warriner,1 then chief engineer, now president of the Lehigh Navigation Coal Co., and stripping methods between 1917 and 1931 were the subject of a paper in 1931 by H. H. Otto,2 of the Hudson Coal Company. . The present paper is confined to methods used today on pitching beds in the western middle and southern anthracite fields. The anthracite industry, not unlike other large industries, had been affected for more than a decade by the adverse economic conditions of the country. High development and operating costs and the competition of other fuels caused some collieries to be closed temporarily, while others were permanently abandoned. In order to obtain a larger tonnage at a lower development cost, a larger stripping program was put into effect by many companies. In 1932, stripping operations accounted for 3½ million tons, or 7 per cent of the total anthracite production of the year, and in the next 10 years this increased until more than double that amount, or over 14 per cent of the total production, was from stripping operations. These figures represent the total production of the entire anthracite region; unfortunately, the figures have not been separated from the different fields. There are some operations in the southern and middle western fields where the tonnage obtained from stripping amounts to more than 30 per cent of the total colliery production. Stripping operations on pitching beds present difficult problems. Owing to the various geological formations, a different situation is encountered in nearly every stripping pit; and because of the proximity of an overlying bed, it is very often necessary to load the entire overburden into trucks and haul it out of the pit to the dump area, although back filling and casting is done whenever possible. Beds in the areas described in this paper pitch from 20" to 90 and some are on the invert in many sharp folds and faults. Planning The more successful strippings have had adequate engineering analysis. Some work is being done without much preliminary planning, but many strippings would have failed completely if close supervision by the engineering department had not been . maintained. Locations of stripping areas are determined as follows: I. By constructing cross sections over the areas and drilling sufficient diamond-drill or well drill holes to study the strata and to determine the location, thickness

Jan 1, 1944

By Park Wright

The fact that granite has been encountered by the drill by those in search of oil and gas in Kansas is becoming more and more a matter of interest, not only to the oil producer but to everyone directly and indirectly connected with the oil business. It is, therefore, time that someone should offer an explanation for its presence and form a definite opinion, based on all the data available, in regard to the effect it will have on the future prospects of the area affected as probable oil-and gas-producing territory. At present there seems to be no consensus of opinion. To the writer's knowledge, only one attempt has been made to explain ; by Erasmus Haworth, State Geologist of Kansas, in a paper entitled Bulletin Number Two on Crystalline Rocks in Kansas. The purpose of the present paper is to offer a theory for the presence of the granite, and to draw conclusions which will aid in determining the prospective oil and gas value of the area in question. In taking up this question it will be well to consider first the tests in which granite has been reported, with a general history of each. The accompanying map (Fig. 1) shows the location of all wells described. The first well in which granite was reported was that drilled just south of Zeandale in section 27, township 10 south, range 9 east, by a local company which had taken up a block of leases in that vicinity. At a depth of 958 ft. (291.99 m.) granite was encountered. Drilling was continued to a depth of 1093 ft. (333 m.) in the same formation, at which depth the hole was abandoned. Another well was started 1 mile east of the first well and the same rock was found at a depth of 945 ft. (288 m.). Drilling was continued to a depth of 1200 ft. (365.76 m.) with the bit in the same formation. Samples of the drill cuttings have been examined and they are undoubtedly crushed granite. The next well in which granite was found was that drilled by DeLaat and Shepard, independent wildcat operators, in section 34, township 19 south, range 7 east, near the town of Elmdale. Granite was struck at 1707 ft. (520 m.) and the hole was abandoned in the same formation at 2525 ft. (769 m.). Mr. DeLaat watched the drilling of this well very closely and he has described to me in some detail the formation immedi-

Jan 1, 1918

Kidd Mine in Northern Ontario is now producing from Stage 1 of the Mine D expansion project ? mining between 2100 m and 2700 m below surface. Planning for Stage 2 of the Mine D project is already well advanced and will see the mine extended potentially to 3100 m below the surface. To ensure adequate ventilation is maintained at such depths, two large axial fans have been installed on the 6000 Level (1800 m below surface) as exhaust booster fans to operate in series with the surface exhaust fans. The Kidd Mine 6000 Level Booster Fans are a unique installation with unique and often unexpected challenges. These challenges have been met and attacked through the combined efforts of mine and fan manufacturer personnel with a common focus.

Jan 1, 2009

By G Haywood

This paper presents the evolution of the planning, scheduling and mining practices at the Yilgarn Star underground. The paper will concentrate on the principals of æjust in timeÆ and the impact of such practices on mine planning and scheduling and subsequent development and production. The principals of æjust in timeÆ were developed to minimise the impact of creep and time dependent failure of the ground in the ore and hangingwall zones. These zones are characterised by altered schistose material with inherent weak rock strengths compounded, at depth, by the maximum principal stress of the virgin stress field approaching the UCS of the rock mass. Yilgarn Star underground has and continues to develop the æjust in timeÆ methodology to ensure the continued viability of the mine. The mine continues to use longhole open stoping mining methods to ensure high levels of productivity with minimal dilution and at an acceptable cost of production.

Jan 1, 2002

By R. D. Brown

On November 16, 1978, Finance Minister Chretien delivered his second formal budget in the House of Commons. Over-all, the provisions of the budget should provide moderate stimulus to the Canadian economy. With respect to the mining industry, the budget offers some welcome changes in the form of' improved write-offs for development expenses and social assets; higher investment tax credits; and a reduction in federal sales tax. On the other hand, income bond financing of new mineral ventures may be restricted.

Jan 1, 1979

By G. A. Gross

"The Soviet Union has enormous reserves of iron ore in many different kinds of deposits that are widely distributed in this vast land area. The present iron ore industry is based mainly on deposits in Precambrian cherty iron-formation at Krivoy Rog, Kursk and Murmansk. Extensive reserves of both naturally enriched hematite ore and magnetite iron-formation in these areas alone could sup-ply all the domestic ore required for several hundred years.Many contact metasomatic magnetite deposits discovery in recent years in the eastern Ural Mountain belt and east of the Kusnetsov basin in Siberia are being developed, with ore reserves measured in billions of tons. Oolitic limonite-chamosite-siderite ores of Cretaceous and younger age at Kerch on the Black Sea and around the east and southern perimeter of the West Siberian basin constitute some of the largest concentrations of iron in the world. These sedimentary ores are low grade, of poor quality and difficult to beneficiate. Banded jasper magnetite and hematite iron-formation in volcanic rocks of Devonian age in Kazakhstan and along the Mongolian border are of special geoloica1 significance.Iron deposits in the Krivoy Rog and Kursk areas were examined and a large number of geologists discussed their work on deposits in many other parts of the Soviet Union during the writer's seven-week study tour of mines and research institutes in Moscow, Leningrad, Novosibirsk in Siberia and Kiev in the Ukraine. The descriptive geology of iron deposits of useable ore and of marginal material has been well documented in the course of systematic work and a large number of scientists are studying fundamental problems on the origin and treatment of iron ore."

Jan 1, 1967

By Akira Ishikuro, Masamichi Shintaku, Futoshi Kusumoto, Takeshi Kudo

"The Bankei-Kitanosawa tunnel that is located in Sapporo, Hokkaido, Japan includes a 450m long section near the arrival point where mudstone which can liquate out natural hazardous materials such as arsenic and selenium exceeding the tolerance stipulated by country as well as weathered mudstone and unconsolidated sedimentary rocks with small overburden and the competence factor less than 1.0 are present. The mucks containing hazardous materials were disposed into the waterproof branch tunnels created from the inside of the main tunnel. The full face early ring closure method was employed to ensure the stability of the tunnel in the low strength rock masses having no stand-up time. As a result, the waterproof tunnels branching off the main tunnel can manage water tightness so as to ensure safety and relief against environmental risks of the hazardous materials. It is also demonstrated that the full face early ring closure method enable construction of the tunnel with a small overburden in the low strength rock masses. INTRODUCTION The Bankei-Kitanosawa tunnel includes a 450m long section near the arrival point where mudstone which can liquate out natural hazardous materials such as arsenic and selenium exceeding the tolerance stipulated by country as well as weathered mudstone and unconsolidated sedimentary rocks with small overburden and the competence factor less than 1.0 are present. In order to overcome the restrictions, the hazardous materials were designed to be disposed into large cross section waterproof tunnels which were newly designed and constructed in high strength and hazardous material free Andesite. The lining for the tunnels was composed of with shotcrete. In addition, full face early ring closure (Sato et al., 2013) was employed to stabilize the tunnel so as to enable safe tunnel excavation in low strength rock masses where a ground arch is deemed unachievable. This paper presents the safe disposal method of mucks which are likely to liquate out natural hazardous materials as well as the full face early ring closure method and its mechanical characteristics."

Jan 1, 2016

The following brief paper is intended, to apply to the concentration of the silver-lead ores at Broken Hill, New South Wales, generally, but more particularly to the process as applied to the ores in the Block 10 mine. The attached plans are similar inmany respects to those prepared, recently for the Block 10 company.Most of the information here given is already well known to those members who are conversant with the concentration practices of this field, but it is the writer's object to give just a few of those figures which he found difficult to obtain when first engaging in practical work. At that time no text-books were at hand from which it was possible to get sufficient details for practical working purposes.It is first supposed that the mine has been thoroughly explored and has been found to contain a lbde sufficient in size ·and quality to warrant the erection of a concentrating plant. The points then to determine are:-(1.) The quantity and cost of water available for steam-making and ore-dressing purposes.(2.) The most convenient site for the mill.

Jan 1, 1904

By D. V. Keller

The use of a static bath of a heavy liquid of intermediate density between two mineral phases has been employed for beneficiation for over one-hundred years (1-6). In the case of the heavy liquid separation of coal from its included mineral matter, laboratory (3) and commercial (2,4) techniques have employed a halohydrocarbon or mixtures thereof, or solutions of inorganic salts and water with a specific gravity in the range of 2.0 to 1.30. As a laboratory tool, the heavy liquid separation is generally regarded as a standard permitting the "ideal" separation of a product coal and reject mineral matter. Each of the products in this case is polyphase since the separation is only based on apparent specific gravity of the product or reject material. The "Otisca Process" is an anhydrous heavy liquid separation process which employs a parting liquid with certain physical and chemical characteristics which make it particularly advantageous for expanding the laboratory separation process into the realm of commercial coal cleaning. The two key characteristics of the parting liquid are: 1) the heavy liquid does not react significantly with the coal product or reject material, and 2) the liquid permits complete dispersion of the coal product particles throughout the separation bath. The first point, i.e., the lack of liquid coal reaction (7-11), may be cited as one of the major reasons for the failure of other attempts at commercialization of heavy liquid processes. For example, if reaction does occur between the heavy liquid and coal or mineral matter, complete heavy liquid recovery becomes a very expensive complex process. The costs of heavy liquids alone prohibit their loss in the process as will be demonstrated later.

Jan 1, 1977

By F. S. Knoll

Electrostatic separation is one of the most misunderstood physical processes used to beneficiate minerals. Nonetheless, millions of tons of titanium ores, iron ores and other minerals are processed every year economically, efficiently and safely. Over the past ten years major advances in electrostatic separation and its application have occurred. New processes include dewatering clay slurries, separating halite and sylvite, and shape separation of vermiculite and gangue minerals. Electrostatic separation techniques are based on one of two methods, electrophoresis or dieleccrophoresis -- processes involving charged and uncharged particles respectively. In some cases, the combination of these two techniques has proven quite useful. The purpose of this paper is to provide a basic understanding of the physical processes collectively called "electro- static separation" in order to enhance one's ability to define and consider new possibilities in mineral processing and other fields.

Jan 1, 1984

By J. G. Baragwanath

CUBA'S lateritic iron ores, occurring on the northern coast of that island, though known to the Spaniards. did not receive any general attention until the close of the Spanish-American War. Preliminary studies of these deposits at that time indicated that the limonite contained small percentages of nickel and chrome, and it ryas subsequently discovered that although the average nickel content was only approximately 0.6 per certain limited areas of ore were suffiniently high in nickel to be considered commercial provided a suitable process fur its recovery could be developed. Early in 1937, Pardners Mines Corp. began a series of investigations which led to the development of such a process. Coincidentally, this company acquired option' on certain properties in the Levisa Bay and Moa Bay regions and conducted a systematic campaign of exploration by test pits and hand-auger holes in the course of which an aggregate of 90.000.000 tons of ore was developed in eight deposits.

Jan 1, 1945

By Lorie M. Dilley

Alaska Village Electric Cooperative (AVEC), an electric utility cooperative providing power to 51 Alaska villages, has made a concerted effort to install wind turbines in the villages they serve in an effort to mitigate the growing costs of electrical power generation. The subsurface soils in several of these villages consist of sands and silts with ground temperatures of between 30°F and 32°F. The presence of warm, degrading permafrost in three of the villages has required innovative foundation designs, including the use of helical piers and piles to support steel and concrete wind turbine foundations. The design of the deep foundations had to account for the effects of degrading permafrost likely resulting from observed climate change patterns. Uplift forces imposed on the foundations were approximately 100 kips per pile. Uplift pile load testing was conducted on the installed piers and piles in order to determine the actual working load that each pier or pile could sustain. In addition, pile driving analyzer testing was conducted on several piles installed in the permafrost and compared to pile load tests. Results indicated that the installed piers and piles achieved the necessary capacity with sufficient factors of safety. Thermosyphons were installed near the foundations in order to limit the effects of climate change on the permafrost. The two to four wind turbines in each of the three villages are currently operational. Refinement of the design based on the pile testing from the first village to the third has decreased the cost of the tower foundations and improved our understanding of designing for warm, degrading permafrost.

Jan 1, 2010

In November 1992, the Internal Revenue Commission (IRC) was formed from the rperggr of the Papua New Guinea Taxation Of- fice (PNGTO) and the Bureau of Customs, and now has the re- sponsibility for the administration of direct and indirect taxes on a national basis in Papua New Guinea (PNG). Since that date we have undertaken many initiatives to make the new organisation more efficient and responsive to clients' needs. Income Tax The mining industry is catered for, in respect of income tax, un- der a separate taxation regime within the Income Tax Act (ITA), Division 10, as well as some general provisions within that Act as may be applicable. Division 10 is itself broken up into subdi- visions to cover the different types of mining leases, namely Spe- cial Mining Leases (SMLs) and Mining Leases (MLs), and peri- ods of time during which those sub-divisions apply. Ring Fencing Income tax assessed on the mining industry, with the exception of Mining Leases (these will be explained later), has a project basis of assessment, that is, each project is assessed separately as if the taxable income of the taxpayer from operations attributable to the project was the only assessable income derived by that taxpayer. This is often referred to as "ring fencing". This is an important point to consider because losses from unsuccessful projects cannot be set off against income from those that are suc- cessful, except in very limited specific circumstances, such as where an unsuccessful exploration licence is cancelled or surren- dered. The project basis of assessment applies to both resident and non-resident companies. A relaxation in the 'ring fence' provisions was applied from 1st January 1995, where ten percent of exploration expenditure, in- curred in areas outside of Special Mining Leases and Petroleum Development Licences in a particular year of income, can be claimed as an outright deduction which is limited to ten percent of the tax otherwise payable in that year. This was introduced to encourage exploration in PNG.

Jan 1, 1997

By M. R. Shadnam

This contribution provides an assessment of research and development efforts to optimize SOx, NOx and mercury capture in flue gas. Coa, characteristics and combustion conditions in a power plant have an impact on the types and concentration of flue gas pollutants. These factors can also affect the amount of pollutant removed. This contribution would also provide a comparative study of the technologies that holistically aim remova, of SOx, NOx and mercury altogether in coal-fired power plants. A portion of this contribution provides background information on regulatory drivers.

Jan 1, 2010

By Yi Yang, Xiuzhu Su, Wei Sung Ng, Shuiping Zhong, Miao Chen

With over 260 tons of gold reserves, the Shuiyindong gold mine is one of the largest Carlin-type gold deposits in China. A particular challenge in the processing of the ore is the presence of carbonaceous compounds, which can cause substantial losses in recoveries via the preg-robbing and adsorption of gold. To investigate the structural properties of the native carbon and to compare between different characterization techniques for such compounds, pre- and post-flotation mineral samples containing 0.9–4.8% non-carbonate carbon from the Shuiyindong mine have been examined via mineralogical and thermogravimetric approaches, as well as spectroscopic techniques, including X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine edge structure spectroscopy (NEXAFS), solid-state 13C nuclear magnetic resonance (NMR) spectroscopy, diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, Raman spectroscopy and preg-robbing measurements. NEXAFS and DRIFT yielded the most reliable results, indicating that 60–75% of the organic carbon in all samples consist of aliphatic alkenes with substantial unsaturated content, highly similar to activated carbon, with the remainder being graphitic and humic. Speciation by XPS was sub-optimal due to spectral overlaps between graphitic and aliphatic carbon, and between carboxylic and carbonate functionalities, while NMR spectroscopy could not provide reliable speciation of the carbon groups. The preg-robbing strength was strongly correlated to the aliphatic content and structural disorder in the carbon, while no such relationship was found with the graphitic and humic content.

Nov 29, 2021

By Stephen Mansfield

In open-pit mining operations, the drill and blast processes have a significant impact on the downstream operational performance of crushing and grinding of ores and recovery of metal. The blast pattern parameters, combined with the material properties, defines the run of mine fragmentation, which in turn drives the subsequent energy requirements for further processing and mill throughput. A common parameter used to describe a single hole or collection of holes is powder factor, the ratio of explosives to the quantity of material blasted. One often-neglected aspect of calculating powder factor is the explosives contained within the length of hole drilled into the top of the bench from the previous bench, known as subdrill. Explosives in the subdrill directly affect the bench below and thus do not contribute significantly to the results of the upper bench, even though they are traditionally included in the powder factor calculation. This paper presents geospatial data modelling methods that link individual holes from an upper bench to the bench below. This enables a new method for the calculation of powder factor, whereby the explosives in the subdrill from the bench above are included in the powder factor calculation of the bench below. This method allows for a clearer understanding of the impact of subdrill on fragmentation, and how variations in blast designs in the upper bench, i.e. hole diameter, burden, spacing, subdrill length, explosive type, primer position, etc., and accuracy of implementation, i.e. actual hole depths and explosive mass per hole, affect the powder factor and blasting results in lower benches.

Feb 6, 2023

By M. N. Pons, F. Ferrari, V. Houzelot, B. Laubie, A. Bani, Université de Lorraine-CNRS LRGP

"More than 400 plants in the world are able to accumulate nickel in their aerial parts at concentrations higher than 10 g per kg of dry biomass. Then, nickel (Ni) can be recovered from the biomass of these hyperaccumulator plants. Agromining is a chain consisting in growing such plants and recovering metal and has been developed thanks to the combined know-how of agronomy and hydrometallurgy. Plants can be grown on serpentine soils, containing rather high concentrations of Ni, on sterile heaps or on contaminated soils. This crop enables us to extract Ni from secondary resources, and to improve soil quality by lowering its metal content. For example, Alyssum murale can be grown at the field scale in the Balkans, at yields corresponding to 110 kg Ni per hectare.Hydrometallurgical processes have been designed from the lab scale to the pilot scale to produce nickel salts: ANSH (ammonium and nickel sulphate hexahydrate), nickel sulphate, acetate, etc. and so on. These salts are used for surface treatment and in the paint and chemical industry. Ni salts are prepared from ashes, after plant calcination. Processes are based on the conventional methods of hydrometallurgy: acid leaching followed by different precipitation steps. These processes will be presented, as well as the pilot scale design. A life cycle assessment has been performed and clearly shows the environmental interest of this approach as a potential part of an anti-erosion strategy. An economic assessment has proved process feasibility and the final step is the launching of a start-up. At the moment, the approach is widened to other metals (cadmium, cobalt) and rare earth elements (REEs)."

Jan 1, 2016