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By D A. McCallum

With depth, many gold ores become sulfidic with minerals such as pyrite, pyrrhotite and arsenopyrite becoming prevalent. In addition, many underground gold mines use tailings backfill to bind and store the waste. In these cases, acid mine drainage (AMD) can become an issue. One approach to the control of AMD is desulfurisation whereby the sulfide minerals are removed prior to disposal. Four sulfide tailings samples, representing different ore types and gold and base metal operations, were selected for assessment and testing using simple physical beneficiation techniques. The aim was to determine the extent to which mineral processing methods were suitable for separating sulfides from non-sulfides and for extracting potentially marketable by-products from the tailings. In order to streamline the testing procedure a simple diagnostic separation technique was developed to enable quick screening of bulk sulfide tailings for suitability for reprocessing. The testing procedure involved detailed characterisation and a sequential set of testing regimes based on simple unit processes including water washing, classification, gravity concentration, magnetic separation and bulk flotation. The preliminary test results indicate each unit process can play an important part in producing effective sulfide/non-sulfide separations and in generating useful by-products from the tailings. Potential valuable products identified include coarse, benign silica sands, bulk iron sulfide products rich in pyrite and/or pyrrhotite, high-grade iron products (magnetite) low in silica, low-volume bulk sulfide concentrates and low-grade molybdenite and talc products. The work presented shows how sulfide tailings can be viewed as a resource rather than a waste stream, and identifies a pathway for developing a more sustainable approach to the environmental management of sulfide tailings for the future.

Jan 1, 2007

Water rights and availability are extremely contentious issues in many mining regions around the world, in some instances leading to violent confrontation. This situation has the potential to only get worse because competition for 'scarce' water resources will increase with population growth. In this environment the dilemma facing the mining industry is how to generate confidence in developing a responsible, sustainable and transparent water management strategy that is recognised as such by all stakeholders. Whilst the water needs of the mining industry are minor compared to those of agriculture, an operating mine requires a relatively large quantity of water on a daily basis to carry out operations. Another contentious aspects of new mine development is the debate between all stakeholders on the amount and quality of water that a mine is able to discharge into the environment should this be required. There are a multitude of water resources available to the mining industry for operational needs however much of this water is saline and over the last two decades there has been a continual decline in water quality (ie salinity has increased). In today's world there are enormous internal and external pressures to reduce water consumption at a mine and/or alternatively use water not considered a resource by the local community (ie sewage, saline or salt water, desalinated water). Strategies to meet these objectives can be achieved by implementing good water management practices, by recycling process water, reducing water losses by evaporation and seepage (ie by increasing and improving dewatering practices) and employing new technologies such as dry stacking and dry processing. Recycled water, acid mine drainage water and water collected in the mining area have the potential to impact mineral processing performance, unless they are treated, because of the build up of mineral salts and decomposed chemical products in these types of waters. Besides this the regulatory requirements of any water discharged from a mine site (quantity and quality) have also become more stringent. For these reasons there is now some form of water treatment practiced at most mining operations around the world. This paper provides an overview of water stewardship undertaken in the mining industry over the last two decades and provides examples of water treatment practices that have recently been installed at mining operations that may be of interest to the reader.

Sep 13, 2010

Low displacement fault zones often comprise a mesh of interlinked faults, extensional-shear and purely extensional vein fractures. Hydrothermal mineralisation localised around such structures testifies to their importance as conduits for fluid flow. Mesh structures are most commonly developed in situations approximating bulk pure shear but predominantly simple shear meshes also occur. They appear to develop through the infiltration of pressurised fluids into a heterogeneous rock mass with varying material properties. In some circumstances, mesh formation appears to be a precursor to the development of major through going faults. Mesh formation generally involves hydrofracturing (Pf > s3, at least locally) and the condition Pf ~ s3 to be maintained for the mesh to remain a high permeability conduit, requiring fluid over pressuring at other than shallow depths in extensional-transtensional regimes. The volumetric character of earthquake swarm activity appears to result from the passage of hydrothermal fluids through mesh structures, representing a form of distributed fault-valve action along suprahydrostatic hydraulic gradients arising from magmatic intrusion, compaction overpressuring, metamorphic dewatering, etc. Fluid redistribution in the crust is influenced by maximum hydraulic gradient (not necessarily vertical), by existing permeability anisotropy arising from bedding and other forms of crustal layering, and by structural permeability developed under the prevailing stress field. Strong directional permeability develops in the s2 direction, parallel to fault-fracture intersections within the mesh and orthogonal to fault slip vectors. In particular tectonic settings, stress-controlled permeability allows strongly focused flow through fault-fracture meshes with high potential for mineralisation. Favoured localities for mesh development include short-lived link structures along large-displacement fault zones such as dilational jogs, lateral ramps, and transfer faults.

Jan 1, 1995

By M I. Pownceby, S Hapugoda, V Nunna

Deposits of low-grade iron ores containing abundant goethite are distributed across the world. A common difficulty associated with beneficiating goethitic-rich ores is the poor liberation characteristics of the iron-bearing minerals which often contain finely disseminated gangue minerals such as kaolinite, gibbsite and quartz. Microwave-assisted heating has been proposed as an effective way of inducing dehydroxylation and associated mineral transformations in order to beneficiate low-grade goethitic ores. In this research, the mineral transformations occurring in a low-grade goethite-rich sample using microwave radiation was studied. Roasting conditions (up to 1000°C and under various CO/CO2 gas atmospheres) were designed to generate a magnetic product from a goethite-rich, reject waste stream sample sourced from an iron ore processing site in the Pilbara, Western Australia. Conditions (T, pO2) for transforming the raw material from hydrated goethite to hematite and eventually to magnetite are presented. Chemical and mineralogical characterisation of the raw material and roast products were conducted using X-ray fluorescence, X-ray diffraction, optical microscopy and scanning electron microscopy techniques to identify the mineralogical and chemical changes occurring during the heat treatment. Further steps are suggested to optimise the microwave-assisted magnetising roasting and correlate it with the application of magnetic separation techniques to maximise the efficiency of upgrading the iron content in low-grade iron ores.CITATION:Nunna, V, Hapugoda, S and Pownceby, M I, 2017. Study of microwave-assisted magnetising roasting and mineral transformation of low-grade goethite iron ores, in Proceedings Iron Ore 2017, pp 575–582 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Kuzmitch O, Morozov A

The main direction in the mechanisation in the mines of the Donbas and the USSR is long-face technology with complexes on the base of hydraulic supports. On the base of the 30 year old experience of exploitation of the coal clearing systems the serious data about the behaviour of the contained rock, display of underground pressure 'on longwalls and preparatory workings have been accumulated. Exploitation works in mines of the USSR are carried out at different depths: from 1000m to 1200m. There are 26 mines in Donbas, which exceed the depth of 1000m. It is the mines of Donbas, where is a rich experience of the exploitation of coal seams in various conditions. Besides, there are wide variations on the factors of the extraction thickness, depth of seam, angle of dip, occurrence of gas dynamics and others. In many scientific establishments, and in Donetsk Polytechnical Institute also, there are scientific research/results, which can be of interest for the coal mining countries.The volume of coal mining from longwall system-mechanised walls in Donbas became stable at the end of the 70s at level of 70 percent. All the efforts to increase this level have not given any notable results, not saying about the technical-economical data, which gradually deteriorate. It shows that positive progress in using the technology for the long walls is over and it is necessary to find new ways of mechanisation of coal winning.

Jan 1, 1991

Tertiary laterite is extensively developed in the Darling Range area, but there is doubt that. the high relief areas along the Darling Scarp have been peneplaned. Three distinct laterite types are distinguished which are termed transported, introduced and residual laterites to avoid ambiguity. Transported laterites are recemented (primarily) lateritic materials and introduced laterites are chemical deposits of bog iron type. Residual laterites are formed in situ from the host material which can be either decomposed bedrock or detrital' clay, and the two varieties formed from these sources are termed residual A and residual B laterites. The genetic requirements for residual laterite formation are (1) host material, (2) porosity and permeability, (3) rainfall, (4) temperature, (5) relief and drainage, (6) vege- tation and (7) time. Previous theories on the origin of laterite appear to be inadequate and incompatible with field observations. Field investigations and drilling in the Darling Range area disclosed lenticular section and thickest laterite development on slopes and thin or oc- casionally no laterite development on crests. Lateritisation is considered a surface feature and the end product of the chemical weathering cycle. The relief and rain-water acting on a kaolinitic host material are con- sidered the major contributing factors in the

Jan 1, 1973

By D Osborne

Current mineral extraction and valorisation activities still have a strong focus on the ‘delivered product(s)’ which might be a bulk commodity such as metallurgical coal, hematite, bauxite, etc., and mineral concentrates such as metal sulphides, oxides, and carbonates; precious metals, such as gold, silver and PGMs, REEs or battery metals; halogen salt forming elements; or industrial minerals, which are non-metals including crushed rock, sand, and gravel etc. With the current focus on tailings disposal the pushback has been to seek alternatives to the currently ‘conventional’ disposal method via increasingly higher risk tailings settling facilities (TSFs) with a changing focus towards ‘dry disposal’. Whichever option is selected, the alarming trend is the increasing cost and ESG impacts. An emerging approach is to pose a focusing question ‘Is there anything else passing into the tailings stream and/or disposable waste streams which could be recovered and pass into the product revenue stream? All of the above ‘primary’ process streams offer opportunities for increasing recovery and offsetting some of the disposal costs. Some secondary opportunities are already being pursued, such as REEs and battery metals from base metals deposits, but other opportunities are still being overlooked, such as building materials and soil conditioning pellets. These potential ‘new’ product streams can also utilise other mining and domestic wastes such as smelting slags, glass waste, plastic waste etc. This paper will address these opportunities and provide examples including process approach, economics and some of the current barriers that exist, which are holding back progress on such initiatives.

Sep 1, 2024

Intermontane valleys form unusual features of compressive mountain belts both in the sharp topographic break they represent and in the strike-slip displacements often associated with the valleys. Such strike-slip motion seems hard to reconcile in the actively deforming Andes where reconstructions have indicated nearly perpendicular Cenozoic plate convergence. Detailed study of a part of the Argentine Andes between latitude 31-33¦S suggests that, although strike-slip displacements may have largely created a prominent intermontane valley system, no Holocene strike-slip displacements are observed amid the relatively active compressional deformation along the mountain belt flanks. New plate reconstructions, treating the Nazca plate as two microplates separated by fractures along the Nazca Ridge, predict large components of strike-slip motion between the South American and Nazca Plates for the period from 10 to 5 Ma. These reconstructed plate motions are consistent with strains derived from recent kinematic analyses of minor faults along the southeast margin of the Puna plateau and the general timing of tectonic phases in the Andes.

Jan 1, 1987

The granitoid rocks in Burma can be subdivided into three main belts viz. (1) Eastern Granitoid Belt, (2) W-Sn related, Central Granitoid Belt and (3) Porphyry Cu (Au)-related, Western Granitoid Belt. The W-Sn related, central belt Granitoids were interpreted to have generated during the continent-arc collision and the Porphyry Cu(Au)-related, western grantioid belt was emplaced in a magmatic-volcanic arc above an east-dipping subduction zone. INTRODUCTION Major tectonic domains of Burma Burma region can be subdivided into N-S trending (6) major tectonic domains from west to east (1) Arakan Coastal Strip as ensimatic Foredeep (2) Indo-Burman Ranges as Outer Arc or Fore Arc (3) Western Inner-Burman Tertiary Basin as Inter-Arc Basin (4) Central Volcanic Belt (Central Volcanic Line) as Inner Magmatic-volcanic Arc (5) Eastern Inner-Burman Tertiary Basin as Back-Arc Basin and (6) Shan-Tennasserim Massif as ensialic, Sino-Burman Ranges (Bender, 1983). The Sagaing (transform) Fault and Shan Boundary Fault form as a tectonically significant boundary between Eastern-Burman Basin (Back-Arc Basin) and continental,

Jan 1, 1987

By N McIntyre, R Trancoso, N Bulovic

Mining is essential for facilitating human development particularly as demand for critical minerals grows. However, over the mine life cycle, the environment is permanently changed. Once mining ceases, mine-affected land can leave significant legacy issues on the surrounding environment if not managed. Therefore, mine closure planning is critical. Mine closure occurs over large scales often with the aim of recreating resilient ecosystems over mined landscapes with mitigated negative impacts. The natural state of the landscape and the environmental risks over planning time-scales are largely driven by climate. Climate change is expected to impact different parts of the post-mining landscape, from stable landform design (soil erosion mitigation) to revegetation efforts and pit lake management. Consequently, mine closure plans may need to account for a non-stationary and uncertain future climate, that may be both different to the current climate and evolve during the mine life and post-closure. Here a new data-based approach is presented for incorporating climate change projections in mine closure planning, based on the recently released Coupled Model Intercomparison Project phase 6 (CMIP6) climate data used in the latest Intergovernmental Panel on Climate Change (IPCC) assessment report. The approach: (i) characterises closure-related attributes of the future climate, and (ii) identifies the amount (and direction) of change expected to occur, and its uncertainty, focusing on five metrics for demonstrative purposes and initially describing changes in erosive potential below. This provides information on the type of future environment (ie the changing baseline) that mine closure should plan towards, and identifies rehabilitation options that may be susceptible to increased risks from climate change.

Aug 2, 2023

Both the miner and the Regional Water Board have legal obligations to ensure that all discharges of water from a mine site are free of harmful wastes, and that proper authorisation is obtained to abstract, divert, or discharge water. This requires long-term planning of water management for the whole of the mine site. Guidance is given in the paper on the issues which must be covered in water right applications.

Jan 1, 1986

By K B. Quast, A Schuurmans

Laboratory batch rod and ball milling tests were conducted on samples of Heavy Medium Separator (HMS) sinks from Renison Limited. The effects of mill rotation speed, rod volume and ball size on the resulting product size distribution were investigated. Between 48 and 69 per cent of critical speed, the product sizing distribution curves remained very similar, with a finer grind resulting from increasing the speed of rotation at constant grind time. Increasing the rod loading from ten to 53 per cent by volume caused the product size to become finer and more closely sized with a transition occurring at approximately 29 per cent. This was interpreted as a change of dominant grinding mechanism from abrasion to impact. No preferential grinding of the cassiterite was observed. The effect of increasing ball size at constant charge weight was to preferentially grind the coarser particles and generate more intermediate sized particles, whereas the product from a mixed ball charge gave a distribution similar to that obtained when a charge containing only smaller balls was used.

Jan 1, 1998

By I Levy

At our Monkland Mine at Gympie, we operate a deep, narrow vein gold mine using hand held equipment, rail mounted haulage and narrow shafts. This is in many respects the old-fashioned way and is well suited most of the orebody geometry exposed to-date. We have also commenced some long hole stoping and we use alimaks for some jobs. The heart of our particular mining style is the employment and retention of experienced miners with remuneration based on productivity. We do our planning/monitoring/supervision down to the level of daily individual productivity. In focussing on cycles per se, we have chosen not to talk about drill and blast cycles or cycles for mine development, stope preparation or drawdown and haulage. Instead we have stepped right back from the operation as presently run and have adopted a very broad view of the mining cycle. We will in this presentation intertwine the ebb and flow of, exploration, project sponsorship, development, production and cash returns to owners. The time line considered spans both history and predicted future.

Jan 1, 1998

By N J. Grigg

Gekko Systems has developed an underground pre-concentration plant (Python) to reduce mine operating costs. Many ores liberate favourably using either high pressure grinding rolls (HPGR) or vertical shaft impactors (VSI). Using these comminution circuits for mineral liberation; rather than for the final recovery process and by utilising a high mass pull, high recovery process route (gravity/flotation), a narrow, low head, compact processing plant was developed that can sensibly be operated underground. The Python underground processing plant can provide a number of advantages for narrow vein mines including lower haulage costs, improved mine call factor and lower operating costs. The focus on fine crushing reduces the power requirement of the plant to approximately 8 kWh/tonne. The Python underground processing plant has been designed to be towed down the decline or lowered down a shaft, and is capable of being installed in sloping, non-linear drives for placement close to the working face. The overall benefit to mining companies of this concept has been estimated to be a saving in mining costs and a significantly smaller environmental footprint.

Jan 1, 2008

By J Johansson, J Lööw

There are many reports about how the new technology will affect our work, sometimes they are utopian but often dystopian. Most of the visions describe the industrial work, while the work of the managers does not seem to be affected. In this article, the authors will discuss how the new technology within the concept of Mining 4.0 changes the conditions for leadership and the work of managers in a modern mining industry.

Sep 1, 2024

By S R. Grano, M Vera

This paper deals with two separate case studies investigating the froth phase performance and characterisation of two industrial rougher/ scavenger flotation circuits. Froth phase performance was quantified using a mass balance approach to estimate froth zone recovery. Measured characteristics of the froth phase included frother solution concentration determined by gas chromatography, and the time taken for an equilibrium froth sample to decay to one-half of its original froth height. The latter measurement is referred to as the æfroth half-lifeÆ and is strongly linked to froth stability. Special methods and techniques developed to preserve frother in solution and to measure froth half-life are briefly described. The frother type in the first case study was a mixture of straight and branched alcohols, whilst the frother type in the second case study was a mixture of alcohols, aldehydes and triethoxybutane. The first case study focussed on a flotation circuit treating a low-grade ore containing only a small fraction of floatable copper sulfide minerals, while the second case study focussed on a flotation circuit treating a higher grade complex sulfide ore containing significant quantities of chalcopyrite, galena, sphalerite and pyrite. It was found that froth zone recovery of valuable mineral generally decreased down-the-bank of the two industrial rougher/scavenger circuits. Moreover, decreases in froth zone recovery significantly limit the overall cell recovery of valuable mineral achievable from the plant scavenger cells. However, the decrease in froth zone recovery could not be linked to the removal of frother from the pulp solution to the concentrate product in the preceding rougher flotation stages. Measurements of residual frother in solution suggested that, approximately, only five to ten per cent of the added frother was removed into the rougher/scavenger concentrate, with the remainder appearing in the scavenger tailings. This finding suggested there was apparently adequate frother in solution in the scavenger stages.

Jan 1, 2005

Zircon is extensively used as moulding sand in the production of steel and high-duty iron castings. To achieve a satisfactory grade of zircon concentrate, the zircon particles may need ,to have surface coatings removed, as such coatings can hinder electrostatic and magnetic separation of zircon from associated minerals. Xn addition the presence of surface coatings on the zircon. particles can cause sinterins and fusion of the zircon to the east metal resulting in "burnt-on" sand or fritting of the casting. "Burnon" necessitates cleaning of the casting by grinding or chipping, which is expensive and results in loss of definition on the casting face.Hudson (1966) has pointed out ,that some coatings on mineral sands are lightly-adhering clays which can be removed quite readily by agitating the sands in water for a few minutes-thus their removal constitutesno problem. However, the heavy gingery coloured coating which adheres strongly to the surface of the particles in some deposits, and which has generally been considered to be a form of iron oxide (Baker, 1962; Hudson, 1966), cannot be removed effectively by attrition cleaning in water (Hudson, 1966). Such coatings limit the usefulness of these concentrates in the foundry industry.An investigation of strongly-adhering coatings on "ginger zircon" concentrates from the Yoganup deposit of Westralian Sands Ltd has shown that the stain consists of a cemented mixtvre of hydrated iron and aluminium oxides and kaolin minerals, and that it can be removed by a relatively low cost treatment.IDENTIFICATION OF THE STAIN BY XRDX-ray powder diffraction (XRD) patterns were obtained from small samples of stain scraped, individually, from the surface of hand-picked zircon and ilmenite crystals. These scrapings were mounted on quartz fibres and exposed to CoKa radiation in a 57 mm Debye camera. To avoid heavy fogging of the x-ray films, a substantial amount of the iron oxides was preferentially leached from the scrapings (before mounting) with an ammonium oxalate-oxalic acid solution (Rooksby, 1961). The residual material gave a fairly well resolved powder pattern (Table 1). A...

Jan 1, 1975

By Stone I

Tahmoor Mine is located in the southern Sydney Basin 80km south-west of Sydney and produces 1.2 MT of Bulli Coal annually. Bord and pillar methods used to date will be supplemented by a longwall system. Difficult roof conditions have been experienced since mining began in 1979. A dominantly horizontal stressfield promotes shear failure in the thinly interbedded roof sequence of shales, laminites, siltstones and fine sandstones. General roof conditions and failure characteristics are related to the angle between the roadway direction and the principal horizontal stress direction. The apparent stressfield changes direction, magnitude and the ratio of principal horizontal components across the mine workings in response to both in situ and mining induced causes. Initial roof support of 5 x 2.1 m bolts per W-strap at in intervals, with mesh, was upgraded to include RSJ's in order to support areas of failed roof. This support system was inefficient and costly. A third system of support emphasizes roof reinforcement with full resin encapsulation of 2.1 m bolts in W-straps. The number of bolts per strap (6-8), extra butterfly straps and bolts, and W-strap spacing is determined for each area by expected roof and stress conditions. Intersections are pre-bolted and ribs are supported in some areas. Pillar dimensions, order of drivage and roadway width have each been altered to improve roof control. The intensity of roof deformation at the face varies from panel to panel and causes development rates to decrease to 30% of the maximum. 1. Manager, Tahmoor Mine, Tahmoor, N.S.W. 2. Senior Geologist, BP Coal, Picton, N.S.W. Roof conditions in each area of the mine are characterised and then projected to future development areas based on the relationship between stressfield orientation, relative roadway direction and face conditions. Planning information available includes expected development rates, roof support requirements and areas of changing conditions. Future improvements of strata control involve defining support design parameters for the range of mine conditions already seen at Tahmoor.

Jan 1, 1986

By G Gibson, B Bessen

In coal preparation, large dense medium cyclones (DMC) at low pressure heads (typically 9D where D = cyclone diameter) are the norm. This contrasts with high density mineral applications where, largely for historical reasons, smaller cyclones at high heads are the standard. There are advantages in preferring large diameter cyclones at low heads, assuming that metallurgical performance does not suffer significantly. These include simpler plant layouts, easier maintenance, smaller spares inventories, reduced wear, reduced medium pumping demands, smaller buildings and overall lower capital and operating costs. In 2008, therefore, Xstrata Zinc decided to trial a single DSM-design 800 mm cyclone in one of its four DMC lines at Mt Isa, replacing the four 400 mm cyclones previously installed. Circumstances allowed a low head of 9.5 D to be trialled, compared with the existing 400 mm head of 21.5 D. This paper describes the trial, including tests using painted ore particles as tracers, estimates of yield and metal recovery, and wear monitoring. The larger unit performed well. There was no evidence that metallurgical performance in terms of metal recovery and waste reject rate suffered, and there was some evidence that it may have improved. Cyclone life increased, and preliminary data suggest that the replacement cost of the 800 mm cyclones is less than half that of the 400 mm units, and this is expected to improve. The plant layout and operability have also improved significantly. Xstrata has therefore decided to convert the whole plant to four low head 800 mm units, replacing the original 16 high head 400 mm units. The paper includes an explanation of the effect of static head on DMC separating force. It also reviews earlier research on diamond applications, and applies a general DMC process model to the Xstrata case, both of which confirm that large, low head cyclones are appropriate in mineral applications, contrary to conventional practice. Such units could significantly reduce both the capital and operating costs of DMC plants in mineral applications.

Jan 1, 2009

By Koppe J. C, Costa J. F C L

This paper compares different results for overburden volume estimation assisted by geoestatistics, particularly using kriging methods. The main goal is to obtain the most reliable digital terrain model for the calculation of the overburden volume. The data was collected on an irregularly spaced grid and interpolated values were calculated to provide a denser, more regular data set before volume estimation. The field work was developed at the Butia-Leste Coal Mine, southern most Brazil, where an accurate survey was done using a total station theodolite with electronic data collector. The study was developed in five main steps: data acquisition, exploratory data analysis, spatial continuity measurements, point and block kriging estimation and verification of the results. Data acquisition was carried out on a 5 x 5 in grid. This dense grid provides an exhaustive data set of the real terrain against which data subsets can be compared for the various interpolation procedures and volume calculation. This provides an interesting insight into the influence of the number of data on the estimation error. Univariate statistics were used to compare each data subset and the exhaustive dataset. Ordinary kriging on the data subsets followed by contouring was carried out using Geoeas and Surfer software respectively. A subroutine written in C provided the link between the files generated in Geoeas and subsequent contouring routines embedded into the Surfer package. Omnidirectional and directional variograms were modelled defining the parameters for kriging estimation using Geoeas. Different variogram models were checked through cross validation prior to kriging. A comparison between the magnitude of the differences in volumes calculated with the different DTMs was attained. These final result indicates the sensitivity of the volume obtained to the number of data points. As the number of data points increases the estimation error decreases, but at some point there is no significant decrease in the final volume with the collection of additional data.

Jan 1, 1995