Search Documents

By Steve Kral

Mining is a risky business. The cost of exploring for new mineral deposits is high and the success rate of finding one worthy of development is relatively low. And once a deposit is identified, there is no guarantee that it will become a mine. Mining companies have to spend a lot of time and money on due diligence, prefeasibility and feasibility studies, and sustainable development and environmental issues before deciding whether the deposit will become a profitable mine. And then there are the millions of dollars spent in developing the deposit and building a mine. No wonder the mining industry has trouble attracting investment capital. Companies take a large risk in developing reserves and investors take a similar risk in investing in them. So mining companies must be as accurate as possible in determining mineralization that makes it to reserve status. After all, reserves are a company’s most important asset and one of the critical factors analysts and funding sources look at when determining if a mine or mining company is worth the risk.

Jan 1, 2003

By M Freeman

In a visionary move, the Planning Commission and the Ministry for Planning in Western Australia decided to invite three extractive industry quarry operators, local government councils and State Government departments (Minerals and Energy, Environmental Protection, South West Development Commission) to contribute jointly to study the impacts of blasting on areas surrounding basalt quarries in the Bunbury region of WA. The results of the study will help establish suitable zones in which land uses will be controlled under a proposed Greater Bunbury Region Scheme and in local planning schemes, to minimise conflicting land uses. This paper discusses the blasting program conducted to characterise and model the vibration behaviour of the rock under the effects of pilot-scale and full production blasting, and highlights some of the benefits achievable when a thorough blasting impact program and assessment is conducted at the planning stages of land-use establishment.

Jan 1, 2001

By E P. Graham

Orebodies occur in an infinite variety of grades, shapes and sizes, and take many millions of years to grow. When extraction starts there is only one possible end -the mine sooner or later will run out of ore and shut down. If the mineral industry is to supply the ever increasing demands of modern civilizations, more and more metals must be found and mined. This will require a never-ending search for ore, and the development of every economic body, large or small. To justify the mining of a small orebody, it first of all must pay its way. If the size of the burden imposed by the capital cost estimates is not carefully worked out, an otherwise promising situation could be killed. The very nature of mining, as a transient industry, re-leases a steady stream of good used equipment, and the trained personnel to install and operate it. All manner of plans and layouts, which can be utilized at a new property, are available. Working these and other economies into the estimates will sometimes make enough difference to give a prospect the green light.

Jan 1, 1964

"Chairman: Dr DeV. HarrisRapporteur: Mr A.H. MunroPapers:Corporate exploration strategies by MacKenzie, B.W.The Engel Simulator and the search for uranium by Griffiths, J.C. and Singer, D.A.The Chairman opened the session by tracing the changes which have taken place in the exploration field since the days of the lone prospector who relied upon his individual skills and to a large extent on luck. The deposits which now remain to be discovered are better covered and are of lower grade. A much greater team effort, involving geoscientists and engineers, is required. The gamble is thus much greater -not only are the probabilities of failure still significant but the consequences are more severe. A recent Canadian survey indicated that expenditures of between two and nine million dollars on regional exploration programs are required to locate one significant deposit.The Chairman went on to say that these facts have led companies to regard exploration as another form of investment and to treat it accordingly. This had placed exploration in the context of corporate strategics and structures, which was the subject of the first paper of the session.In introducing his paper, Dr B. W. MacKenzie said that the paper suggested a decision framework for exploration planning. Initially the environment is analyzed to define observable and relevant economic characteristics. The terms of reference for exploration planning and the appropriate allocation of capital and skills are then established in the light of corporate objectives and growth alternatives. With the aid of this information and in the light of profit and corporate risk criteria, exploration strategies can be selected.Dr MacKenzie went on to say that the usefulness of the concept and criteria outlined in his paper depended critically upon three characteristics of any particular economic environment, namely, the return resulting from an economic discovery, the unit discovery Cost and the probability of making an economic discovery. He then showed by means of a case history relative to the Canadian Shield and Cordilleran areas that these three characteristics could, in fact, be evaluated for regions with reasonable histories of mineral activity.The first contributor to the discussion of the paper, Mr Alfred Weiss, mentioned that his group had been involved in exploration modelling for some ten years and were thus particularly interested in the paper. He went on to say that they had experienced greatest difficulty with reconnaissance programs and that he sensed that these difficulties were also present with the methodology which had been outlined. Mr Weiss asked Dr MacKenzie how he would deal with such situations when no information was available but where there was the potential for both exploration and discovery. Dr Mackenzie agreed that the lack of information was a very severe limitation and said that at the present time his methodology probably did not provide a basis for breaking down the broad geological regions he considered into areas for further assessment."

Jan 1, 2014

By D. R. Derry

"IT WOULD TAKE a braver man than I to try to forecast the future of mining exploration far into Canada's second century. Even to look ahead ten or twenty-five years we must review the figures of the fairly recent past -and I have found this quite a time-consuming but interesting job -in order to find trends and project them into future years. The trends to which I will refer are: firstly, the annual expenditure on exploration and its relation to value of output; secondly, the discovery rate and its relation to production initiations; and thirdly, the methods by which discoveries have been, and will be, made. Exploration Expenditures Figures on the annual expenditure on mining exploration in Canada have been collected and published for some years by the Do-minion Bureau of Statistics. These have some unavoidable limitations; e.g., in the varying definition between one company and another of what comprises ""Exploration"" and in the difficulty of getting complete returns. However, although the actual figure for a given year may be subject to question, I believe that the relative figures from one year to another are reasonably reliable. There is also a lapse of time between the collection of data and publication -the last published figures are for the year 1963. In bringing the figures up to date to 1966 I have canvassed eight of the larger mining and exploration companies and obtained their figures for 1963 to 1966 inclusive, and then averaged these for each year and applied the progression to the 1963 figures."

Jan 1, 1968

By E. D. Attanasi, J. H. DeYoung

Several factors contributed to continued declines in mineral-exploration activity in the US in 1985. Low metal prices and, what appears to be worldwide chronic excess capacity in copper, molybdenum, lead, and uranium, have resulted in mineral-exploration expenditures remaining anemic. Economic recovery could result in a healthier mining industry and more cash flow to fund exploration. This is because general economic activity and US mining industry activity have historically been closely linked. However, as the worldwide economic recovery has expanded, the mining sector has continued its downward slide. New cuts in industry exploration budgets in 1985 shocked those who thought the exploration situation could not become worse. Some personnel and equipment had been redirected from base metals exploration to precious metals in the past few years. Last year, continued reductions in exploration sent many professionals out of the mining industry. Recent staff reductions or consolidations of operations were made by Noranda, Chevron, Molycorp, and other exploration companies. The latest data from the Society of Economic Geologists (SEG) summary of exploration statistics show that professional staff at year end in major US exploration companies (domestic and foreign operations) fell from 2355 in 1981 to 1868 in 1983 and 1277 in 1984. By the end of 1985, two economic trends were established that could improve the future profitability of mining and hence exploration. First, the price of crude oil began a decline. If sharply reduced energy prices increase worldwide economic expansion, the substantial excess capacity in some of the base metals industries could disappear, and prices could improve. Furthermore, if energy price declines reduce mining and processing costs significantly, metals may recapture some lost markets. The decline in oil revenues has already encouraged some oil-producing countries, such as Venezuela, to look toward development of mineral resources to earn foreign exchange for debt repayment. Second, the decline of the dollar by 21% during 1985 could also help US producers meet foreign competition. During 1985, industry restructuring continued as many oil companies sold off mining subsidiaries and minerals properties. Gold, silver in new discoveries Precious metals continued to dominate the announcement of new discoveries and exploration projects in 1985. A review of domestic exploration and development activities reported in several industry journals shows that 60% to 80% of these projects were directed primarily at precious metals, particularly gold. Base metals exploration activities frequently involved polymetallic deposits with gold or silver values. Because much of this exploration was done on identified targets (on-property exploration), the decrease in wildcat or grassroots (off-property) exploration may be more substantial than indicated by reductions in total exploration activity. Significant gold discoveries in 1985 included several in Nevada, among them the Genesis property of Newmont (near the Carlin mine), Goldfields' discovery of the Chimney deposit in Humboldt Co., and Freeport's discovery of two mineralized sites near Jerritt Canyon. Gold exploration continued to be focused in the western US and Alaska, but gold production starts at the Haile mine in South Carolina, and the Ropes mine in Michigan as well as Amselco's feasibility studies on deposits near Ridgeway, SC, are evidence that gold exploration is not limited to the West. The dominance of gold projects in exploration is not limited to the US, as demonstrated by gold dis¬coveries and exploration projects in Australia, Brazil, Canada, the Caribbean region, China, Guinea, Ivory Coast, South Africa, the South Pacific islands, and Thailand. From the standpoint of US metal miners, it is perplexing that worldwide exploration and development is also taking place in copper, zinc, tungsten, and other metals with depressed prices. During 1985, the US Geological Survey's efforts to map the sea floor of the Exclusive Economic Zone shifted from the Pacific Coast to the deep water areas of the Gulf of Mexico and to areas off the coast of Puerto Rico and the Virgin Islands. An atlas containing sea-floor maps of the west coast area was published as US Geological Survey Miscellaneous Investigations Series Map 1-1792. Results of the 1985 surveys are expected to be published by January 1987. Exploration trends - Statistical evidence Data from the SEG showed continued decline in the US mining industry's exploration expenditures through 1984. The share of US companies' domestic exploration expenditures directed toward base and precious metals has increased from 51% to 84% from 1980 to 1983 and to 86% in 1984. US mining companies spent about $0.67 of each exploration dollar in 1984 in the US. However, this represents an increase from earlier years. The 1983 data also show that firms spending more than $5 million on exploration accounted for 77% of exploration expenditures. Since 1981, the Bureau of Land Management (BLM) has been assembling data on claims and an-

Jan 5, 1986

By Brent C. Jellicoe, Phil Robertshaw, J. Murphy, Peter Williamson

Kimberlites and associated diamonds have been the focus of extensive exploration in central Saskatchewan since 1988. During 1989, Uranerz Exploration and Mining Limited identified 71 shallow magnetic anomalies in the Fort a la Corne area from detailed aeromagnetic surveys. By the end of 1991, 18 of these targets had been proven, by drilling, to be kimberlite bodies encased within Cretaceous sedimentary strata. From 1991 to 1997, the number of drill-confirmed kimberlite bodies increased to 69. Our current view, drawing on an integration of geophysical and geological information, is that the kimberlites are composed of individual bodies and multi-vent clusters of coalesced bodies, all apparently constructed of stacked, temporally distinct layers of pyroclastic crater-facies kimberlite. Diamond recoveries and geochemical results from associated heavy minerals at Fort a la Corne remain highly variable, although continued minibulk sampling is expected to improve the estimation of diamond grades for the most prospective bodies.

Jan 1, 2001

By D Giles, A C. Bailey

In the first 20 years of the 21st century, just over 20 per cent of Australian mineral exploration expenditure was dedicated to iron ore, totalling >A$8 billion and >30 million metres of drilling (Australian Bureau of Statistics, 2021). Improvements in the cost, efficiency, safety, reliability and data quality of drilling have the potential to deliver significant productivity improvements, increasing the probability of discovery and reducing the time from discovery to mining. Currently in its third year of research, Mineral Exploration Cooperative Research Centre (MinEx CRC) is focused on a new set of exploration tools and new ways to deploy those tools which recognise the fundamental importance of collecting quantity and quality data from the subsurface, to enable exploration success for all minerals, including iron ore. MinEx CRC is focused on developing more productive, safer and environmentally friendly drilling methods to discover and drill-out deposits. This includes pioneering work on Coil Tube (CT) drilling technology and innovations in Diamond and Reverse Circulation (RC) drilling techniques aimed at improved drilling optimisation and automation. In parallel, MinEx is developing new technologies for collecting data whilst drilling. This is being undertaken in four separate industry-led projects utilising geophysical, seismic, downhole analytical and 3-dimensional (3D) modelling improvements. A National Drilling Initiative (NDI) is also underway, with two drilling programs completed in 2020. The NDI is a world-first collaboration of Geological Surveys, researchers and industry, which undertakes drilling in under-explored areas of potential mineral wealth in Australia and provides a test-bed for new mineral exploration technologies.

Nov 8, 2021

By W. Edwin Dill

For the mining industry, the Internal Revenue Code and regulations offer a range of choices in arriving at the allowable depletion. Each case is essentially unique. Two prerequisites can optimize these opportunities: communications between the mining company's tax specialists and its technical staff; and an understanding of IRS definitions. For the latter, a logical starting point is consideration of exploration and development, since they precede production and depletion is unallowable prior to production. Criteria for selecting engineering and accounting options for exploration and development indicate the necessity of interaction between these company functions to achieve the most favorable tax position.

Jan 1, 1982

By Fredrick C. Kruger

We can confidently predict such obvious long-term trends affecting the minerals industry as - increasing consumption, exhaustion of easily discovered near-surface ores, and sharp limitations upon open pit mining by environmental considerations. There- fore, we must intensify the exploration for, and the development and exploitation of, deep bodies of potash and other ores. This paper examines the state of the art of the search for, and the evaluation of, potash from both a geological bias and a mining practicability. The use of indirect geological methods and geophysical techniques, followed by expensive deep drilling, are the conventional approach to evaluation and development of mining plans. The geologist and the geophysicist will have to find ways to perform both of these tasks better and cheaper.

Jan 1, 1973

By E. Harrison

The Greens Creek Ore Bodies are located approximately 18 miles southwest of Juneau, Alaska in an area on Admiralty Island classified as a non-wilderness national monument. An area-wide stream sediment geochemistry program targeted the deposit in October of 1973. Today, after 37,000 meters of combined surface and underground diamond drilling, three ore zones are known to exist with total reserves approaching 4.1 million tonnes. Lying within moderately folded metasediments of an undetermined age, these orebodies are thought to be of seafloor exhalite orgin and contain unusual and impressive amounts of gold, silver, lead, zinc and copper.

Jan 1, 1986

By T Blenkinsop, A Jenkins, H Moore, L Fisher, N Oliver, J Cleverley, M Nugus, J McLellan, J Hill, N Brunacci

The 2 Moz Vogue mineral resource is a recent discovery at the Sunrise Dam gold mine (SDGM), lying approximately 600 m vertically below the Sunrise Dam open pit. Unlike most other lodes, which are dominated either by steep vein sets or shallow high-strain (shear) zones, it lies broadly in the hinge of a folded felsic porphyry body, where it cuts intermediate volcanic lavas and volcaniclastic rocks and is not specifically concentrated at a lithofacies contact. The mineralisation is controlled by a complex interplay of moderate to shallow, west-dipping high-strain zones that are transected by irregular and discontinuous high-grade, north-west-, north–south- and east–west-trending breccia sheets that initially caused problems with attempts to model broad domains. However, by combining the structural controls and styles with the distribution of gold, arsenic, sulfur and antimony, we have improved opportunities for scheduling, extracting and processing the most appropriate material considering the current mining and processing constraints.The early delineation process for the Vogue lode revealed a significant mineral resource for the SDGM, coupled with the recognition of some potentially difficult downstream implications for mining and processing. The ultimate success of mining at Vogue will be a consequence of combining standardised data collection and geological modelling techniques with the results of the novel innovative techniques applied at an early stage of the project.Innovation (in the truest sense) drives change and application to deliver efficient and effective outcomes. Initial data generation and interpretation in lodes above Vogue provided a sound geological model based on strong structural foundations, leading to ideas that could be tested and validated by stress inversion analysis and modelling simulations. Geomechanical modelling simulations, based on the structural analysis, then provided an insight into both the structural and fluid evolution of the system and highlighted target areas. This promoted support for deeper drilling and sampling, which lead to the discovery of Vogue.With additional data, the structural model for Vogue was re-engineered through combination with geochemical and hyperspectral analysis and detailed geological and geostatistical domaining. Initial poor results from metallurgical tests from a small batch sample refocused efforts to undertake mineral and chemical characterisation and profiling (geometallurgy) and combine this data with the composite geological-structural-geochemical model. The result is a conditional probability model for differentiating mineralised or waste domains, with direct outcomes for planning, drilling and mining.CITATION:Nugus, M, Oliver, N, Blenkinsop, T, Hill, J, McLellan, J, Cleverley, J, Fisher, L, Brunacci, N, Moore, H and Jenkins, A, 2014. Exploration and innovation – the discovery and evolution of the 2 Moz Vogue Gold Resource, Sunrise Dam Gold Mine, Western Australia, in Proceedings Ninth International Mining Geology Conference 2014 , pp 323–340 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By D Pearce

The 15-year long debate between the industry, Government and Aboriginal people about the rights and wrongs of Land Rights, the right of Aboriginal people to control development on their land and the relationship between the parties, has been long and often bitter. It has so far been a war of words and often the truth has been the first casualty. This paper looks at the debate and presents the perspective of Aboriginal people, as well as looking at how the industry and Aboriginal people can work together for everyone's benefit. It addresses such matters as: ò why Aboriginal people believe they have the right to control development on their land; ò the perception that Aboriginal people are anti-development; ò the perception that Aboriginal land is 'locked-up'; and ò how companies can negotiate with Aboriginal people.

Jan 1, 1994

By J F. H Thompson

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Mineral exploration and mining are challenging businesses. Remote and at times harsh conditions have always made it difficult for exploration, but modern explorers also have to deal with cover, numerous technologies, an explosion of data and critical early community engagement. Mining deals with the reality of moving and breaking thousands of tonnes of rock each day to extract what can be a very minor component of economic value, and, furthermore, society expects that this will be done in a clean and sustainable manner. The exploration and mining challenges appear disparate, but they are intimately related.Although not widely appreciated, both exploration and mining have a long tradition of innovation. Over the last 50 years, major step changes in exploration have resulted from radical advances in our understanding of ore forming processes, new geophysical, geochemical and remote sensing technologies, and new ways to integrate and interrogate data. Over a more extended period, close to 100 years, mining has developed bulk surface and underground methods, selective extraction through flotation and leaching and global positioning system–geographic information system control systems that collectively facilitate mining at a massive scale. And yet, in spite of these successes and the boom that we have enjoyed in the last ten years, the industry is under pressure and the need for innovation and change is paramount.The major drivers for innovation are the need for increased quality in discoveries and mines and the need to interact effectively with communities and jurisdictions such that the benefits of quality mines are recognised and enjoyed widely.We are still making new discoveries around the Pacific Rim and elsewhere, but many argue that the quality – grade and accessibility – of these discoveries is decreasing. The net result is that explorers are delivering resources and reserves for development at lower grades and with higher capital and operating costs than current operations. For mining, the increasing age of many existing operations contributes to increasing costs, which, when combined with decreasing cut-offs and lower grades, also results in declining quality. The combined picture does not look good.Just as the pressure to improve performance and margins in the face of declining inputs increases, we are simultaneously faced with increasing societal demands for improved environmental performance and sustainable practices. This is most apparent at the local, community level, where opposition ultimately leads to delays or even cancellation of new projects. Quality is again the issue – quality of the initial and ongoing engagement and quality of the proposed mine in terms of environmental and economic performance.CITATION:Thompson, J F H, 2015. Exploration and mining – the need for innovation , in Proceedings PACRIM 2015 Congress, pp 45–48 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By G. P. . RiddIer

The ninth symposium in the series 'Prospecting in areas of glaciated terrain' was organized by the Institution of Mining and Metallurgy in association with the British Geological Survey and was held in Edinburgh from 2 to 4 September, 1991. Dicussions of sessions are presented.

Jan 4, 1992

By Stephen J. Juras

The Myra Falls deposits comprise a complexly metal-zoned polymetallic volcanogenic massive sulfide district located 90 km from Campbell River in central Vancouver Island, British Columbia, Canada. The massive sulfide deposits are hosted by subaqueously-deposited rocks of the Devonian age Myra Formation of the Sicker Group volcanic assemblage. The deposits comprise many individual massive sulfide lenses grouped into several major zones within two main felsic volcanic stratigraphic intervals - the upper Lynx-Myra-Price Horizon and the lower H-W Horizon. The largest of these zones, the H-W and Battle, occur within the H-W Horizon. The first claims in the area of what is now Boliden-Westmin?s Myra Falls Operations were staked in 1917. Early prospecting resulted in the discovery of three massive sulfide showings which eventually became the Lynx, Myra and Price mines. Sporadic exploration was carried out until 1961 when Western Mines Ltd. (now Boliden-Westmin Ltd.) acquired the claims. Subsequent ore definition outlined 1.9 million tonnes of ore (approximately 5 years of mine life) in the Lynx deposit, and mining began in 1966. Pre-mining geological reserves (to January 1, 1997) comprised 6.7 million tonnes grading 3.3 g/t Au, 130.6 g/t Ag, 2.0 % Cu, 1.4 % Pb and 10.2 % Zn for the Lynx-Myra-Price deposits, 17.1 million tonnes grading 2.3 g/t Au, 32.7 g/t Ag, 2.3 % Cu, 0.3 % Pb and 4.2 % Zn for the H-W deposits and 4.2 million tonnes grading 1.1 g/t Au, 27.0 g/t Ag, 2.2 % Cu, 0.5 % Pb and 12.0 % Zn for the Battle deposits. Property-wide production to January, 1996 has been 15.7 million tonnes grading 2.1 g/t Au, 58.7 g/t Ag, 1.9 % Cu, and 5.2 % Zn.

Jan 1, 1998

Energold Drilling Corp. is a leading specialty drilling company servicing the mineral and energy sectors in the Americas, Africa and Asia. Energold specializes in mineral exploration in remote locations with limited infrastructure. Such locations require the smallest footprint possible going in, leaving as little or no evidence on their way out. Energold?s rigs can be transported by helicopter or manually on footpaths as narrow as 1 m (3.3 ft). They set up quickly and then are struck and packed out, with any sign of their presence quickly disappearing behind them. Energold has teamed up with Atlas Copco and its team of engineers in North Bay, Ontario to design small rigs capable of drilling to a variety of depths, as required for each project.

Jan 1, 2013

By Loris S. Pascoli

The increased pace of globalization in the mining industry has presented more opportunities for Canadian service companies to participate in ventures abroad. However, varying cultures, laws, competitive environments and contracting philosophies in other countries make it impossible to take for granted what is normal in the Canadian context. The author discusses some of his experiences and situations encountered in over 30 years in the diamond drilling industry, the last third of which were primarily focused on projects outside of this country.

May 1, 2001

By John S. Cummings

In this paper the phrase "exploration for blind metal deposits" refers to exploration activities geared to the discovery of metal deposits which cannot be located by visual surface inspection. The word "system" refers to all of the components (people, money, corporations, techniques, etc.) which collectively result in an exploration process. The details of the system or systems which I have employed in exploration will not be discussed because of client relationships. However, some of the more severe problems in exploration result from how the system's components interact and our attitudes as to what exploration data is telling us, if anything. It is these items which will be discussed. Exploration for blind metal deposits, which has been relatively intense over the last 2S years compared to rather minor outlays prior to World War II has often been an uncoordinated assortment of various specialists employing various techniques (see Dickerson -1). In a program geared to the location of blind deposits, the lack of outcropping deposits or occurrences should not be a deterrent to a well conceived and well planned program. The severe cyclical swings in exploration activity, although often coinciding with depressed metal prices, by and large result from the failure of exploration operators to present a coherent and realistic program to management. It is my opinion that the stream of complaints criticizing management for cyclical exploration support are mostly unwarranted, as many of the programs and goals are ill defined. Although depressed market conditions may serve as the catalyst for exploration cuts, the underlying cause is that when the "chips are down", the non-directional, non-specific nature of many programs is revealed. Thus management should not be castigated for eliminating such programs during bad times, but rather they should be castigated for supporting them during boom periods.

Jan 1, 1978

By Ted H. Eyde

Nearly 17 years ago a major producer of synthetic zeolites started an extensive exploration program for natural zeolite deposits which resulted in the discovery of over 170 occurrences in the western United States. A few years later several of the other producers and consumers of synthetic zeolites also started similar exploration programs. Since then, small quantities of natural zeolite minerals have been produced from at least 12 deposits in the United States. Of these the Bowie deposit, about 13 miles north of Bowie, Arizona, is the most important,having produced over 5,000 tons of vitric tuff zeolitically altered to the mineral chabazite and minor amounts of the minerals erionite and clinoptilolite. Mining Districts and Mineral Deposits of Arizona compiled by Charles A. Mardirosian, Consulting Geologist, estimates the value of the total production from the Bowie deposit at a very conservative $2,000,000. Unfortunately, none of the companies responsible for the discovery and the initial production of natural zeolites made any effort to develop the high volume, low cost applications of this unique mineral raw material. Instead, they developed only the high unit value uses to supplement their existing synthetic molecular sieve product lines. With the producers of synthetic zeolites thinking in pounds and not in tons, further development of natural zeolite deposits stagnated for over a decade.

Jan 1, 1974