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By J. H. Swisher

An experimental study has been made of the possible mechanisms for foam stability in the system CaO-SiO2-Cr2O3, where Cr2O3is the foaming agent. The degree of lowering of surface tension by Cr2O3 was determined at 1600 "C for high -silica melts. Measurements were also made of foam stability under standardized conditions. The results of the two sets of measurements then were correlated by applying the Gibbs and Marangoni theories of film elasticity. It was demonstrated that the Marangoni elasticity effect is probably the largest single contributor to foam stability, although the high uiscosity of' silicate melts makes some contribution in controlling the rate of drainage of liquid from bubble lamellae. ThE tendency of metallurgical slags to foam has frequently been observed during steel-refining operations. In the open-hearth furnace,this tendency is considered undesirable because it slows down the rate of heat transfer from the burners to the molten-metal bath. On the other hand, it is sometimes desirable to have a "foamy" slag in the basic oxygen converter.' A more effective blanket over the steel bath is made by a "foamy" slag, and loss in yield of metal due to splashing is minimized. In addition, a flush slag can be removed more easily in this condition. Since slag-foaming problems in the field have been attacked largely on an empirical basis, it appeared desirable to obtain a better basic understanding of the mechanism of foam stability. The experimental work was directed almost entirely toward the behavior of Cr2O3 as the foaming agent in CaO-SiO,-Cr2O3 melts. In the first stage of the investigation, the degree of lowering of surface tension by Cr2O3 was determined at 1600°C. The second stage consisted of measuring foam stabilities under standardized conditions. The two sets of experimental results then were correlated by applying various theories of foam stability. For convenience in interpreting the surface-tension and foam-stability results reported here, a portion of the CaO-SiO2-Cr2O3 phase diagram2 is reproduced in Fig. 1. EXPERIMENTAL 1) Surface-Tension Measurements. Very little information is available in the literature on the lowering of surface tension of slags by foaming agents. Kozakevitch 3 mentioned that the addition of 1.5 pct Cr2O3 lowered the surface tension of FeO slightly. In another system, some data on the lowering of surface tension of foaming slags by P2O5 were reported by Cooper and Kitchener.4 The technique used for the surface-tension measurements was the maximum bubble-pressure method,' using a single tube immersed to various depths in the melt. This method has been used extensively in high-temperature systems, such as in liquid metals, slags, and glasses.6,7 It has the advantage that the contact angle between the liquid and the tube material need not be known. The equation used for calculating surface-tension values from maximum bubble-pressure measurements is the Schroedinger equatioq5 which can be written as follows:

Jan 1, 1964

By Samuel Hoyt

SOME of the more important properties of finished materials are strength, ductility, toughness, resistance to alternating and repeated stresses, etc: Of these, the property that appears to have received the least consideration, at least in this country, is toughness, which is clue, possibly, to our regarding toughness as a qualitative property or, at any rate, as one that, parallels ductility. This arises out of our greater experience with the simple carbon steels in the rolled or forged (non-heat-treated) condition which, qualitatively, are tough if ductile and are not tough if brittle. In this way we have erroneously become, accustomed to judging the toughness of a material from its behavior in the tensile or similar test. The point of view presented in the present paper is that toughness, like hardness or tensile strength, should be regarded as an independent property and of sufficient importance to require, in so far as that may be possible, quantitative determinations. If such be true, it becomes at once necessary to devise experimental means for measuring, or valuating toughness, and the notched-bar impact test (the Charpy test) is advanced as the most logical test that has so far been developed for this purpose. It is further advanced, with particular emphasis, that we have two kinds of toughness to deal with and, accordingly, they will be dealt with independently. CLASSIFICATION OF MATERIALS ACCORDING TO TOUGHNESS Toughness has been defined somewhat as follows: Tough materials are those that offer considerable resistance to permanent deformation but which, once such resistance has been overcome, may' be deformed plastically, but only by the expenditure of considerable energy. In other words; tough materials may be deformed plastically but they absorb a considerable amount of work in the process. This kind of toughness may be called "static" toughness when the rate of loading is reasonably slow or "dynamic" toughness when the rate of loading is

Jan 2, 1919

By E. Nickel

"Bi- and multilateral banks as well as export credit agencies in the OECD countries, but also numerous commercial banks, last year committed themselves to compliance with the World Bank’s standards. These environmental and social guidelines, also known as the Safeguard Policies, are the strictest international standards in the area of financing of major investment projects. The Safeguard Policies are procedural and quality guidelines by means of which socially and environmentally relevant impacts can be taken into account in the planning and implementation phase of a project. Objectives of the Bank Safeguard Policies are to ensure that environmental and social issues are evaluated in decision-making, to reduce and manage risk of projects and programs, and to provide a mechanism for consultation and disclosure of information. They are often referred to as the "10+1 Safeguard Policies," since ten of the guidelines address environmentally and socially relevant issues, while one guideline is exclusively concerned with public participation ("Public Disclosure"). In the presentation, the transparency of risk management measures and emergency response plans in pipeline projects will be discussed as an indicator of sustainability. The discussion is to be carried out on the basis of the results of an evaluation of several major pipeline projects, which have been financed at least in part by multilateral banks over the past few years. The controversies surrounding some of these projects due environmentally and socially relevant impairments connected with the investments have also been addressed by the Extractive Industry Report of the World Bank. Pipeline construction was the investment type chosen for the examination to be presented here, since pipelines frequently start in remote, unspoiled regions, and their routes often cross various natural zones and areas with various social structures. The question of safety during construction and operation of the line is always central to these projects; not only for the responsible authorities but also for other societal groups involved, such as environmental associations."

Jan 1, 2005

By R. N. Chakravorty

Early detection of spontaneous combustion is of utmost importance in underground coal mining to prevent major disruptions of production and to ensure a safer working environment. This paper presents the work done in developing a suitable system for the early detection of heating in a hydraulic coal mine. Laboratory studies on the products of oxidation for Balmer 10 seam coal showed that a significant amount of carbon monoxide is produced during the early stages of heating and that detection methods based on the analysis of other gases, such as hydrogen, ethane or ethylene, are not a better alternative for this coal. The four-point carbon monoxide monitoring system recently installed at the hydraulic mine is discussed in this paper. It is believed that by studying the trend of carbon monoxide concentration in the mine air, it will be possible to detect heating at an early stage. Field tests carried out so far have indicated that infra-red technology will prove to be a powerful tool in the hydraulic mine, particularly for locating hidden oxidation or fire in cracks, fissures, underground workings and coal outcrop areas before it spreads extensively. The project is jointly sponsored by EMR, CANMET, Mining Research Laboratories and Kaiser Resources Ltd.

Jan 1, 1978

By Franz Kolmbauer

At Primetals Technologies Brazil Ltda. Rio de Janeiro Santa Cruz Workshop we electroplate mold coppers for continuous casting by tank plating. Tank plating submerges the copper in the bath of the plating solution. This is the most common method of plating and is applicable for both broadface and narrowface copper plates. Mold copper plates have a decisive impact on the product quality as well as the cost for maintenance and production. A perfect understanding of the operational influences on the plates and performance variables are the first step for the right selection of a copper plating method. Variable Hiper Coat keeps the Copper Plates 50% up to 100% longer in operation because of applying hardness on the Copper Plate where it is needed. Primetals Technologies Brazil provides the solution which meets and exceeds the requirements for todays and future demands.

Aug 16, 2017

By Abegail Endraca, Allan Sebastian, Andrew Raine, Allan Patdu

The project involves the construction of a new aqueduct tunnel by an Earth Pressure Balance TBM tunnel for the Novaliches-Balara Aqueduct No 4 (NBAQ4) project in Metro Manila. It comprises a 7.3 km long and 3.1 m internal diameter tunnel that can deliver up to 1,000 MLD of raw water and the tunnel passes under urban residential and urban populated areas adjacent to and along Commonwealth Avenue. A new reservoir intake structure was constructed in the La Mesa reservoir by a cofferdam and the TBM breakthrough connected the reservoir to the outlet surge shaft structure and the downstream pipe network system connecting to the Balara Water Treatment Plant. The TBM incorporated a double articulated head configuration to allow tight 80 m radius curves to navigate some of the difficult alignment considerations. The alignment passed very close to some existing foundations for MRT7 and needed to clear several tight curves to remain within government land ownership. The project excavated through the local Guadalupe weak rock formations and there was minimal ground movements observed as a result of the work.

Jun 13, 2023

By Michael J. Lawrence

"The VALMIN Code was developed and formally adopted by The Australasian Institute of Mining and Metallurgy (AusIMM) in 1995 and a revision was issued in 1998. The VALMIN Code applies to all relevant reports under the Australian Corporations Law, including submissions to the Australian Stock Exchange (ASX) and the Australian Securities and Investments Commission (ASIC).The VALMIN Code and Guidelines sets standards for the preparation and commissioning of independent assessment and/or valuation reports on mineral and petroleum assets or mineral and petroleum securities.It is mandatory for AusllvI:M's members to follow this Code in these relevant circumstances and failure to do so will result in serious sanction of the member by the Ausllvllvfs Ethics Committee. Public support for the use of this Code has been given by regulators (ASX/ASIC) and market participants ( eg major accountancy firms). It is also endorsed as a guide to general best practice in project assessment and valuation.This paper will discuss how the VALMIN Code has worked in practice over the past few years. It will also examine areas where the Code could be improved and how it could form the basis of a new Canadian Code for mineral property valuation."

Jan 1, 2003

By Mark C. L. Patterson

Hydrothermal brines are extracted from significant depths below the surface of the earth and arrive at the surface at elevated pressure and temperature. The exact chemistry and conditions of these brines depends upon the rock formations through which the water travels, but many of the brines are rich in dissolved minerals especially silica which is often saturated in the brine. At pressure and temperature the minerals remain in solution but in order to extract heat from the brines, they need to be cooled and during which many of the minerals precipitate causing problems. Where precipitation is a problem in the downstream processing, the brines are maintained at a high enough temperature and pressure so as to avoid precipitation and injected back into the geothermal formation. This results in a significant loss in potential energy that could be recovered from the geothermal brines. If left to precipitate in an uncontrolled manner, many of the minerals will precipitate as gels, in a high surface area form which is difficult to extract from the liquor and which can causes problems. Precipitation in this manner often builds up on the inside of pipes, reducing the pipe cross-section available for fluid flow and reducing the overall efficiency of the plant. If the brines are seeded at the appropriate time or the precipitation conditions are changed, mineral particles can be grown and separated more easily from the brine. During this precipitation and growth phase the chemistry of the local environment can also be altered to grow more valuable particulates. Some of the specific chemistries will be discussed with reference to known geothermal brines and what needs to be done to precipitate value added products. A theoretical approach to the complete extraction of minerals from geothermal brines is also discussed with the goal of extracting more heat from the brine prior to reinjection into the well.

Jan 1, 2006

By E. F. Johnson, V. O. Naumann, D. P. Bossler

A method is presented for calculating individual gas and oil or water and oil relative permeabilities from data obtained during a gas drive or a waterflood experiment performed on a linear porous body. The method has been tested and found both rapid and reliable for normal-sized core samples. INTRODUCTION Individual oil and gas or oil and water relative permeabilities are required for a number of reservoir engineering applications. Chief among these is the evaluation of oil displacement under conditions where gravitational effects are significant, such as a water drive or crestal gas injection in a steeply dipping oil reservoir. Numerous proposed methods of obtaining relative permeability data on reservoir core samples have been too tedious and time consuming for practical use, or have yielded questionable and sometimes inconsistent results. A method has been developed by which the individual relative permeability curves can be calculated from data collected during a displacement test. The method is based on sound theoretical considerations. Using this method, with a properly designed experimental procedure, relative permeability curves can be obtained using core samples of normal size (i.e., 2 to 3 in. in length and 1 to 2 in. in diameter) within a few days after receipt of the core. In a recent publication D. A. Efros1 describes an approach to the calculation of individual relative permeabilities that is based on the same theoretical considerations. We believe the approach described in the present paper is more adaptable to practical application than the method implied by Efros. In addition, comparisons with independently determined relative permeabilities are furnished to substantiate the reliability of the new method. DERIVATION Previously the theory of Buckley and Leverett as extended by Welge2 as been used to calculate the ratio of relative permeabilities. In the derivation which follows, this theory is further extended to permit calculation of the individual relative permeabilities. The theory assumes two conditions which must be achieved before the method is applicable. They are that the flow velocity be high enough to achieve what has been termed stabilized displacement,3 and that the flow velocity is constant at all cross sections of the linear porous body. In stabilized displacement the flowing pressure gradient is high compared with the capillary pressure difference between the flowing phases. The high pressure drop insures that the portion of the core in which capillary effects predominate will be compressed to a negligibly small fraction of the total pore space. The assumption of constant flow velocity at all

By W. E. Uren

The Dominion Coal Board was created by Statute passed on July 17th, 1947, and was brought into effect by proclamation on October 21st, 1947. It is, consequently, a comparatively young body, having been in existence for only eighteen months. Before dealing with the constitution and duties of the Board, it may be well to answer the unspoken question of why it has been considered necessary to single out coal as one specific mineral requiring the continuous attention of a specially created permanent Board. In Canada, coal has been the neglected sister of the more spectacular minerals and it comes as a surprise co many to note that in 1948 the value of the coal produced in Canada was higher than that of any other mineral with the one exception of gold. Coal touches upon our daily lives in many different places of which the public are not generally conscious. As household fuel, it is a necessity of life in this northern climate; as a source of steam, it provides the heat for most of our industries; it is the food of the 'iron horse' chat shuttles our persons and our goods across the land; it is the source of power in many parts of the country; it is the chemical reducing agent chat, in our furnaces, transmutes the metallic oxides to the virgin metal. Coal is, in fact, the indispensable mineral chat forms the corner-stone of our present structure of industrial civilization. Is it, then, such an odd thing that the provision of an adequate supply of coal should be a matter of national interest or that measures should have been taken by government co provide for a constant watch, by a permanent Board, on the supply of co al? ? The Board is the result of the recommendations of the Royal Commission on coal which made a long and detailed study of the Canadian coal problem. It is composed of a permanent Chairman and six part-time members, most of whom have had intimate contact with various phases of the industry.

Jan 1, 1949

By J. F. T. Agapito, R. R. Goodrich

Yield pillars have been used for many years to help reduce stresses near mine openings and improve roof and floor stability. A yield pillar is often defined as a pillar that fails but retains residual strength. Stress transfer occurs through the roof and floor after the peak strength of the pillar is reached. High stresses are transferred from around the openings onto abutments that can be barrier pillars or unmined ground. This mechanism, often referred to as pressure arching, is possible as long as the width of yield pillars is less than the critical width above which stresses cannot be carried by the overburden. Significant stress transfer also can occur due to small amounts of pillar and/or floor yielding before the peak strength is reached. This is accomplished in a quasi-elastic manner with little or no visible roof and pillar fracturing or floor heave. Long-term stability may be achieved when stresses and mechanical properties are favorable to pre-failure yielding. This paper gives practical examples where improvements in stability and resource recovery were achieved with this mechanism. Yielding was assessed by comparing measured and calculated vertical pillar stresses. Results indicated that calculated stresses in the pillars were 25 to 40 percent higher than the measured stresses, demonstrating significant arching load transfer to the abutments. Pre-failure yielding is probably often present but unintentional in both development and production areas. Better recognition and use of this mechanism should lead to improved designs as mines become deeper.

Jan 1, 2001

By Grant R. Brown

The report provides guidance for determining those environmental impacts associated with the surface mining of steeply pitching coal seams. In addition to the environmental impacts, four additional issues are addressed, namely (1) Time and motion studies of those coal mining systems employed in mining seams which pitch in excess of 250, (2) Assessment of those mining techniques, (3) Development of rationale for the mining methods employed, (4) Identification of the reclamation practices and determine whether these practices were in compliance with appropriate Federal and State regulations. Five surface mines located in three geologically distinct basins of the United States were analyzed during the period of August through November 1979. The three basins include the Hanna Basin of Wyoming, the North Park Basin of Colorado and the Southern Anthracite Field of Pennsylvania.

Jan 1, 1980

By O. Koatlhai

Mine closures have traditionally prioritised environmental rehabilitation, often overlooking the deep socio-economic disruptions that follow, particularly in mining-dependent communities. This paper argues that mine closure should not mark the end of prosperity but rather the beginning of a sustainable transition. The coproduction model, which integrates community participation, governance, and economic planning, offers a transformative approach to closure planning. Drawing on case studies from Ghana, Zambia, and Indonesia, this research examines the successes and failures of past closures, highlighting the critical role of stakeholder engagement, skills development, and economic diversification. By incorporating emerging technologies such as AI-driven economic forecasting, blockchain for governance transparency, and decentralised finance (DeFi) models, mining companies can ensure a just and sustainable post-mining future. This study challenges outdated closure models and presents a forward-looking strategy that sees mine closure not as an endpoint, but as a catalyst for social resilience and economic transformation. It underscores the need for policy reforms, stronger governance, and investment in alternative industries to prevent mining towns from becoming economic wastelands. By shifting the paradigm from remediation to regeneration, this research calls for a new era of mine closure planning that puts people and prosperity at its core.

Apr 25, 2025

By T. E. Bernard

Occupying a refuge alternative (RA) is an accepted practice in mine fires and explosions when escape is not feasible. MSHA has promulgated a final rule on refuge alternatives that includes a recognition that thermal environment is an important consideration. To this end, an environmental index was specified. The question remains about how to test a refuge shelter to demonstrate that it meets the final rule. The analysis followed five activities: A. Provide an estimate of heat generated by an individual refuge alternative occupant; B. Evaluate the Steadman Apparent Temperature criterion of 95°F; C. Discuss simulations based on body temperature or skin temperature limits; D. Suggest method of simulating human heat generation during refuge occupancy; and E. Suggest alternative methodologies/criteria for evaluating heat and humidity survivability inside a refuge alternative.

Feb 27, 2013

By J. Hu, F. Lin, R. Chen, F Peng, S. Yang, W. Yu

"Microseismic monitoring technology has become one of the most effective method of mine ground pressure monitoring after decades of development. But safety assessment of mine ground pressure by using microseismic monitoring is still in the development stage, it needs to be perfected continuously in practice, and choose the optimal assessment indexes and methods. The definitions and physical meanings of wave velocity, b value, and EI-VA value are introduced in this paper. Statistical calculation of the microseismic events in Luomu Mine is finished by using these indexes, then the functions and calculation results of V, b value, and EI-VA value with the variable of time are also given in the paper. The preliminary safety assessment method is established in Luomu Mine, and it has achieved good results in practical application.1.1 Engineering background The Luomu Mine is a super large molybdenum and tungsten production base in China, ore reserves is up to 2 billion tons, first in Asia and third in the world. It begins mining since the 1960. and bases on underground mining until 2002. In order to recover resources more effectively, it began to use opencast mining method and formed a production of 30000t/d in the early 1990. After about 30 years of underground mining, a large mined out spaces was formed under open pit mine, up to area of 1.2 million m2 and volume of 18 million m3, as shown in figure 1. The large number of mined out spaces seriously affects the normal production, mining and handling of mined out spaces are in the high risk. In the past years, several rock mass collapsions happened, and it caused a serious security threat to persons and equipments. According to the distribution characteristics of mined out spaces, Luomu Mine is divided into A, B, C, D and E mining area. The stability of D mining area is studied in this article. D mining area mainly includes 1376,1350,1340,1317 mined out spaces and 1280 deep large mined out area, as shown in figure 2. The mined out spaces of D mining area is extremely complex and high-risk. Therefore, a microseismic monitoring system was built to monitor the stability of D mining area, a large number of valuable datum has been obtained, and it has a striking effect (Cheng & Peng, 2013; Peng et al., 2013)."

Jan 1, 2015

By Jessica M. Wempen, Dallan J. Coons, Bailey S. Simmons, Michael K. McCarter

Gate-road yield pillars are subject to increases in stress as the longwall face advances toward the pillars. Increases in pillar stress can be inferred by measuring roof/floor convergence surrounding the pillar. This paper presents a case study of convergence measurements surrounding a two-entry gate-road yield pillar in the head gate of a coal mine. Convergence was measured over a six-month period, as the longwall face approached and passed the pillar. Measurements were collected at eight locations surrounding the pillar: four locations in the travelway and four locations in the beltway. In addition to convergence stations, the pillar was instrumented with an array of seismometers. In future analysis, convergence measurements will be compared to seismic interpretations. This study reports on the geology and geometry of the longwall panel, the roof and rib support, the change in convergence over time, and the physical properties of coal and parting. Additionally, the convergence measurements are compared to pillar safety factor distributions derived from a finite element model. The convergence measurements contribute to the knowledge of when yield pillar abutment loading, caused by the encroaching longwall, is first detected. Knowing when abutment loading begins to yield the pillars can help define when standing secondary roof supports are required for head gate entry support.

By S. D. Hill

To help insure the continued viability of the minerals and materials sector of the U.S. economy, the Bureau of Mines is conducting research and disseminating technology that will result in more efficient minerals extraction. As part of this effort, a process is being investigated that involves an aqueous chlorine-oxygen leaching procedure to treat complex sulfide concentrates to produce ZnCl2. Subsequent fused-salt electrolysis of the ZnCI2 produces high-purity zinc metal. Previous reports described preliminary, small-scale research on the chlorine-oxygen leaching system and fused-salt electrolysis of ZnCl2. This report discusses the details of design, construction, and longterm, continuous operation of both monopolar and bipolar fused-salt cells. The effects of temperature, electrode gap, current density, electrolyte composition, and electrode configuration on current efficiency and energy consumption were determined for a ZnCl2-KC1-NaCl electrolyte system. Zinc metal was produced at the rate of about 50 lb/day in a monopolar cell which was operated continuously for 60 days with current efficiencies from 85.8 to 98.6 pct and an average power consumption of 2.1 kwhr/lb. Bipolar cells with several different electrode configurations were operated for 90 days. A current efficiency of about 70 pct and power consumption of about 1.7 kwhr/lb of zinc were achieved using a three-electrode-pair, bipolar assembly with a chlorine gas lift pump to circulate electrolyte.

Jan 1, 1981

By John J. Laffin

"Nova Scotia Department of Mines and Energy Throughout the history of Nova Scotia, trends in the production and use of its coal resources have resulted in major impacts on the economy and society of the province. Current trends in coal demand locally, nationally and internationally are having and will have an increasing positive effect on Nova Scotia over the next twenty years-in terms of energy supply, job creation and general economic development. Coal for electrical generation is an immediate and key objective of Nova Scotia's energy plan; and, in the long term, coal-derived fuels will meet the province's needs for transportation fuels. Demand for metallurgical coal is also expected to increase, especially if the merchant coke plant currently under investigation becomes a reality.Meeting these coal supply and utilization objectives in the face of increasing environmental, social and economic constraints poses a tremendous technical challenge. Work has begun on projects to expand coal production capacity and to adapt new technologies for coal preparation and utilization to the specific needs of Nova Scotia; much more work will be required in the coming decade in order to succesfully tap this resource.IntroductionThe energy problem facing Atlantic Canada has a few unique features not found in the rest of the country. Canada, as a whole, has access to a diverse mix of energy resources, including crude oil, natural gas, coal, hydro and uranium, with the result that crude oil supplies only about 40 per cent of Canada's primary demand. In contrast, foreign crude oil dominates Atlantic Canada's energy mix, supplying over 70 per cent of the primary energy demand.This results in important differences in various sectors. Nationally, about 5 per cent of the electricity is generated from oil whereas last year in Nova Scotia approximately 40 per cent of the electricity generated was from imported oil. Residential, commercial and industrial space heating, and industrial process heating in Atlantic Canada was almost 100 percent dependent on foreign oil. This is in sharp contrast to the situation in central and western Canada, which have access to secure domestic natural gas, oil and hydro electricity."

Jan 1, 1982

A Study on Main and Interaction Effects of Operating Variables of Column Flotation

Sep 13, 2010

By Pablo Velasco

The Belize economy recorded modest growth during 1980; the growth of the gross domestic product (GDP) in real terms was between 1% and 2%. At current prices, the 1980 GDP reached $108 million2. This output was largely attributed to the performance of a few industries, mostly nonminerals. Such performance improved significantly the balance of payments situation by reducing the deficit from $19 million in 1979 to $4 million in 1980. The rate of inflation was an estimated 18% in 1980 and would have been greater if not for a conservative monetary policy and price control on a number of essential items. Expert earnings increased $43 million, or 50%, from the 1979 level. After increasing more than 25% in 1979, imports increased only 6% in 1980 to a level of $141 million owing to the decline in investment and stabilization of petroleum prices. The balance of trade deficit was $9.8 million in 1980, a marked improvement from the 1979 level of $45.1 million. The mineral output for Belize accounted for only a fraction of 1% of the GDP. Such activity was limited to the production of limestone, marl, and sand and gravel, all of which were primarily used in construction of the Northern Highway between Orangewalk and Belize City. Mineral resources are deficient or nonexistent in Belize for the majority of metals and nonmetals, although the Government and others continue to believe that petroleum must exist in Belize. The proximity to Mexican oilfields and the growing finds in the Peters area of Guatemala support this expectation. The Government continues encouraging exploration onshore and offshore and offers terms that

Jan 1, 1982