Industrial mineral resources of Zambia

Zambia has for many years been heavily dependent upon the mining of copper which, combined with cobalt production, represents over 98% of mineral sales and 75% of export earnings (1997 figures). The industrial minerals industry within Zambia has therefore been inevitably tied to the fortunes of these two metals. The recent privatization, and break up, of ZCCM (Zambia Consolidated Copper Mines) has led to a resurgence in investment in the mining sector. Many analysts have predicted that there will be a positive effect on the Zambian economy, stimulating construction and infrastructure development and increasing the demand for industrial minerals. This paper summarises the available information on the industrial mineral resources of Zambia. Ten industrial minerals are described, with reference to some of the work carried out over recent years by the British Geological Survey, in conjunction with the Geological Survey Department of Zambia

Afghanistan : revival and redevelopment

Major redevelopment projects in Afghanistan are placing large demands on the minerals industry, which is struggling to keep pace. Clive Mitchell and Antony Benham report on the revival of the country’s industrial minerals industry

Quarry fines minimisation : can we really have 10mm aggregate with no fines?

In 2005, 216 million tonnes of saleable aggregate was produced in the UK; a corresponding 55 million tonnes of quarry fines and 24 million tonnes of quarry waste were also produced. The need to minimise fines production is driven by the Aggregates Levy (which has priced quarry fines out of the market in favour of recycled aggregate) and the Landfill Tax (which has made it expensive to dispose of fines). Attempts to reduce fines production often start with a process optimisation audit; the case study presented illustrates how fines production can be reduced, in this instance by up to 30%. Application of good practice in the crushing plant also helps to reduce fines production, including: reducing the crushing ratio to 6:1 or lower; maintaining uniform feed distribution; choke feeding (for compression crushers); reducing the speed of impact crushers; and reducing the degree of recirculation by increased screening efficiency. Future developments are likely to be driven by the need to respond to climate change. New crusher designs will be more automated, offer improved energy efficiency, have a greater production capacity and improved reliability

Strict specifications: UK frac sand potential

The UK is actively looking at the potential production of shale gas and, as a result, the country’s extractive minerals industry is looking at the role it can play in providing minerals that could be used in hydraulic fracturing (fracking). One such mineral is silica sand, which is used as a proppant,commonly referred to as “frac sand”. Clive Mitchell, Industrial Minerals Specialist*, provides an educated guess as to where this frac sand could come from in the UK

Aggregate carbon demand : the hunt for low-carbon aggregate

Construction projects are increasingly concerned with environmental sustainability. Schemes such as the BREEAM Green Guide include ‘mineral resource extraction’ as part of their environmental impact rating of construction materials, such as aggregate. One means of assessing environmental impact is to determine the 'embodied energy' used (or 'embodied CO2' emitted) to produce aggregate; this is equivalent to the 'carbon footprint' of an operation. This ‘energy audit’ takes into account everything from extraction and processing through to offices and workshops and waste and water management. The Mineral Products Association publishes embodied CO2 (as kilograms per tonne, kg/t) figures for aggregate, crushed rock, sand and gravel, ready mixed concrete, asphalt and cement. The leading aggregate producers report embodied energy (as kilowatt hours per tonne, kWh/t) or embodied CO2, or even both. Research at the British Geological Survey has been carried out to quantify the likely embodied energy of aggregate resources without the use of an energy audit. A modified work index (‘crushability’) test device has been used to determine the embodied energy of aggregate resources. The initial research has focused on Carboniferous limestone as worked in central and northern England. The ultimate aim is to provide baseline information on the likely ‘carbon demand’ of as yet unworked aggregate resources. This could be presented as spatial data complementary to existing, digital, mineral resource maps. These data will assist in future spatial planning for crushed rock resources and bring a fresh perspective to Mineral Policy Statement 1 which requires that the environmental benefits and constraints of working mineral resources are considered

Geology from home

Many geologists are used to spending at least part of their working lives in the outdoors – but all that changed in March 2020. Clive Mitchell from the British Geological Survey shares his experience of working from home during the current Coronavirus (COVID-19) outbreak

Rural livelihoods and community-based aglime production

The presentation 'Rural livelihoods and community-based aglime production' was a summary of the research caried out into the small-scale production of agricultural lime using appropriate technology. This research was carried out by the British Geological Survey in collaboration with the Zambian Geological Survey Department and the University of Zambia

Social media guidance for British Geological Survey staff

Social media guidance for British Geological Survey staff Social media is a great way to communicate BGS science, activities, achievements and services. This guidance is for BGS staff using social media as a way to communicate BGS science and technology. It is based on the Social Media Guidance for Civil Servants (Cabinet Office, 2012) the NERC Electronic Communications Policy (NERC, 2013) and the NERC Code of Conduct. This guidance was first published in Broadcasting the science stories of the BGS: The British Geological Survey Communication strategy (Mitchell et al, 2014)

REFILL: low-cost fillers from quarry waste

Leahill Quarry is located on the coast of SW Ireland (near Adrigole, Co. Cork) in an Upper Devonian gritstone (fine-grained sandstone) sequence that is worked to produce high specification crushed rock aggregates (exported into UK and mainland Europe). The nature of the rock results in large quantities of fines being produced during processing. Leahill Quarry produces about 270,000 tonnes per annum of fines (0-2mm materials) and ‘filler’ (material passing 75m) after processing (washing). In an attempt to find new outlets for Leahill fines, Tarmac Fleming and BGS took part in a three year EC–supported industrial research project called REFILL, which included other UK and Greek partners and was managed overall by MIRO (Mineral Industry Research Organisation). Further details on the project are available by contacting MIRO through their website at: www.miro.co.uk. The REFILL project consisted of various tasks which involved both Tarmac Fleming and BGS. Tasks 1 to 3 involved a study of existing production practices and a programme of technical evaluation of the fines from Leahill and other quarries in Britain. This involved characterization of the mineralogical, physical and chemical properties of the residues. Task 4 was a large-scale continuous test at Leahill Quarry to determine the effectiveness of a novel fluidised bed plant in terms of its ability to extract ‘filler’ from the 0-2mm fines. Tasks 5 to 8 investigated the potential end uses that could incorporate Leahill filler and fines, including an assessment of the available resources of fines, the availability of fines acceptable for particular applications and a review of the market potential for end-uses including asphalt, concrete, artificial soils and non-plastic sub-base materials