African Eagle Resources plc

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Technical Glossary:

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Alteration

Modification of the chemistry and mineralogy of rocks by the passage of hydrothermal fluids.

Archaean

A geological era lasting from about 3800 to 2500 million years ago.

The chemical symbol for gold.

BIF

Banded iron formation. A distinctive type of rock often found in greenstone belts, consisting of repeated thin layers of iron oxides alternating with bands of iron-poor shale and chert.

The chemical symbol for copper.

Cut-off grade

The grade used to separate ore and waste such that only material classified as ore will be treated in order to recover the economic metal or mineral of interest.

Diamond drilling

Drilling using a water-cooled rotating hollow diamond-tipped bit, cutting a core through the rock which can be brought to the surface by a core barrel.

Feasibility study

A study of the economic viability of the mining and production of base or precious metals or other minerals in such form and containing such detail as is customarily required by a bank or other financial institution engaged in mining project finance to enable it to determine whether to finance the development of a commercial mining operation.

Flotation

A method of separating ore mineral grains from other materials using surfactant chemicals to entice them to adhere to bubbles in an aerated mixture of crushed ore in water, allowing them to be skimmed from the surface of the mixture

Foot Wall

The name given to the host rock of an ore deposit that is physically below the ore deposit

g/t

Grams per tonne

Geophysics

The investigation of the rocks of an area by measuring variations in their physical properties, especially their magnetism, radioactivity, density and electrical properties.

Gossan

The intensely oxidized, weathered or decomposed uppermost and exposed part of an ore deposit or mineral vein.

Grade

The tenor or concentration by weight of a metal in a mineral deposit or ore

Granite

A coarse grained igneous rock high in silica, which usually forms large intrusive masses.

Greenstone belt

Zones of metavolcanic sequences with associated sedimentary rocks that occur within Archaean and Proterozoic cratons between granite and gneiss bodies. The belts often contain ore deposits of gold, silver, copper, zinc and lead.

Hanging Wall

The name given to the host rock of an ore deposit that is physically above the ore deposit.

Hydrothermal

Pertaining to the passage of hot water through rocks. Important in mineral exploration because hot, often superheated, water can dissolve and carry metals, and later precipitate them to form mineral deposits.

Indicated Resource

A category of Mineral Resource of higher confidence than an Inferred Resource, the estimation of which is prescribed by the JORC Code. This is the minimum level of resource classification required for Ore Reserve estimation under the JORC Code.

Inferred Resource

A category of Mineral Resource the estimation of which is prescribed by the JORC Code. Inferred Resources cannot be used as a basis for Ore Reserve estimation.

IOCG

Iron-oxide-copper-gold. A class of mineral deposits characterised by extensive hydrothermal alteration and mineralisation associated with certain granites and other intrusive rocks.

Induced Polarisation. A geophysical prospecting method which measures the induction of electrical charge on the surfaces of conducting mineral grains such as metal ores, within the Earth.

JORC Code

Australasian Code for the Reporting of Exploration Results, Mineral Resources and Ore Reserves (Joint Ore Reserves Committee, www.jorc.org/main.php)

Kansanshi

A copper-gold deposit near Sulwezi in the Zambian Copperbelt, which has several characteristics setting it apart from other deposits of the belt. It is being mined by First Quantum.

Katangan

A supergroup of rocks dating from the Neoproterozoic which is widespread across central Africa and contains the Central African Copperbelt.

Kimberlite

A class of volcanic pipes, dykes and craters which result from explosive eruption of rocks derived from very deep sources, driven by violent de-gassing. Kimberlites are the principal source of diamonds, which are formed at the high pressures at very great depth and are carried to the surface intact by the very fast ascent and cooling of these eruptions.

Kriging

A class of methods of estimating mathematically the distribution of a metal in three dimensions within the earth, together with the confidence of the estimate

Leaching

The extraction of metals from pulverised ore by dissolving them in a chemical solution, especially the extraction of gold using sodium cyanide.

Measured Resource

A category of Mineral Resource of higher confidence than an Indicated Resource, the estimation of which is prescribed by the JORC Code

Median

A statistical estimate of the central tendency of a set of values, with half the values being more than and half being less than the median value.

Mesoproterozoic

A geological era lasting from 1600 to 1000 million years ago.

Metallurgical

Relating to the study of the extraction, processing and properties of metals and their ores

Metavolcanic

Volcanic rocks which have been metamorphosed by heat and / or pressure within the Earth.

Mineralogy

1. The study of minerals.
2. The mineral composition of rocks and ores

Mineral Resource

An estimated tonnage and grade of mineralisation in the ground determined as prescribed by the JORC Code

Model block

A finite 3D element of the Earth for which the average grade can be estimated from drill data

Million Tonnes

Neoproterozoic

A geological era lasting from 1000 to 542 million years ago. During the Neoproterozoic there occurred the most severe worldwide glaciations in the Earth's history, believed to have been so extreme as to bring icecaps to the equator, leading to a state known as the "Snowball Earth".

Ore Reserve

That part of a Mineral Resource which can be demonstrated to be worked profitably when all modifying factors are taken into account.

Percussion drilling

See RAB and RC

PGE or PGM

Platinum Group Elements or Platinum Group Metals. Six metals (ruthenium, rhodium, palladium, osmium, iridium, and platinum), which have similar physical and chemical properties, and tend to occur together in the same mineral deposits.

ppb

Parts per billion by weight (ie milligrams per tonne)

ppm

Parts per million by weight (ie grams per tonne)

Pre-collar

Use of the cheaper and faster reverse circulation method to drill the upper parts of deep holes, before switching to diamond drilling to intersect an anticipated mineralised zone. The pre-collar part of a drill hole is usually expected to be barren of significant mineralisation.

RAB

Rotary air blast. Percussion drilling using a pneumatic hammer, cutting the rock into chips which are flushed to the surface through the space between the drill pipe and the wall of the hole.

Reverse circulation. Percussion drilling using an air-cooled bit, cutting the rock into chips which are flushed to the surface through a double walled pipe by the air pressure.

Recovery

The percentage of a metal which can be successfully extracted from its ore by a particular chemical or physical process or a combination of processes.

Reef

Old miners' name for a gold-bearing zone, usually a gold-bearing quartz vein.

Roan

The lowermost component of the Katangan Supergroup, deposited between 880 and 750 million years ago. Most of the copper deposits of the Zambian copperbelt occur within the Roan.

Shear zone

A linear zone of fracturing and tearing of the rocks which can provide passage for hydrothermal mineralising fluids

Tonne

A metric tonne of 1000 kilograms, abbreviation t

Ultramafic

Igneous rocks with very low silica and potassium content but high in iron and magnesium, usually composed of greater than 90% mafic minerals (dark coloured minerals with high magnesium and iron content).