Geological/Exploration Terms

 

Terminology

In Brazil, the primary system of measure is the Metric System or SI System. Length is commonly expressed in kilometers, meters, or centimeters, while volume is expressed as cubic meters. Mass is measured in metric tonnes, and copper and cobalt grades are typically expressed as a percentage. While older work assessment files almost exclusively refer to the Imperial System, many geologic publications and recent work assessment files now utilize the SI system.

 

"Assay" - the chemical analysis of mineral samples to determine the metal content.

"Basal Conglomerate" - a conglomerate formed at the earliest portion or a stratigraphical unit.

"Bornite" - copper iron sulphide (Cu5FeS4), an important copper ore mineral.

"Breccia" - coarse clastic sedimentary rock, the constituent clasts of which are angular.

"Carrolite" - copper-cobalt sulphide (Cu (Co, Ni) 2S4), an important cobalt ore mineral.

"Chalcopyrite" - copper sulphide (Cu Fi S2), a major ore of copper.

"Clast" - article of broken-down rock.

"Closure" - this involves the application for a closure certificate and initiation of transfer of ongoing care and maintenance to third parties.

"Concentrate" - a product in which valuable minerals have been enriched (concentrated) through mineral processing.

"Contingencies" - this allows for making reasonable allowance for possible oversights/omissions and possible work not foreseen at the time of compilation of the closure costs. An allowance of between 10 percent and 20 percent would usually be made based on the accuracy of the estimations.

"D Strat" (Stratified Dolomite or Dolomie Strafite) - this is well-bedded to laminated, argillaceous dolomite, which forms the base of the traditional Lower Ore Zone in Gécamines' nomenclature.

"G/t" - grams per tonne (one tonne is 1000 kilograms).

"Grade" - the measure of the concentration of copper or cobalt within the mineralized rock.

"Indicated mineral resource" - that part of a mineral resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a reasonable level of confidence. It is based on exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes. The locations are too widely or inappropriately spaced to confirm geological and/or grade continuity but are spaced closely enough for continuity to be assumed.

"Inferred mineral resource" - means that part of a mineral resource for which tonnage, grade and mineral content can be estimated with a low level of confidence. It is inferred from geological evidence and assumed but not verified geological and/or grade continuity. It is based on information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes which may be limited or of uncertain quality and reliability.

"Lithology" or "Lithogical" - geological description pertaining to different rock types.

"Measured Mineral Resource" - means that part of a mineral resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a high level of confidence. It is based on detailed and reliable exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes. The locations are spaced closely enough to confirm geological and grade continuity.

"Metasedimentary" - metamorphosed sedimentary rock.

"Mineral" - a naturally occurring inorganic substance typically with a crystalline structure.

"Mineral Resource" - a concentration or occurrence of material of economic interest in or on the earth's crust in such form, quality and quantity that there are reasonable and realistic prospects for eventual economic extraction. The location, quantity, grade, geological characteristics and continuity of a mineral resource are known, estimated or interpreted from specific geological evidence and knowledge. Mineral resources are sub-divided in order of increasing geological confidence, into inferred, indicated and measured categories.

"MW" - refers to a megawatt.

"Mwashya" or "R4" - altered stratified greyish siliceous dolomitic rock with oolitic horizons and a few bands of light yellow talcose schist.

"Ore" - a mineral or rock that can be worked economically.

"Ore or Mineral Reserve" - the economically mineable part of a measured and/or indicated mineral resource. It includes diluting materials and allowances for losses, which may occur when the material is mined. Appropriate assessments and studies have been carried out, and include consideration of and modification by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. These assessments demonstrate at the time of reporting that extraction could reasonably be justified. Ore or mineral reserves are subdivided in order of increasing confidence into probable ore or mineral reserves and proved ore reserves or proven mineral reserves.

"Orogeny" - an orogeny is a period of mountain building leading to the intensely deformed belts which constitute mountain ranges.

"Outcrop" - rock unit exposure at the surface.

"Probable Ore Reserve or Probable Mineral Reserve" - means the economically mineable part of an indicated, and in some circumstances, measured mineral resource. It includes diluting materials and allowances for losses that may occur when the material is mined. Appropriate assessments and studies have been carried out, and include consideration of and modification by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. These assessments demonstrate at the time of reporting that extraction could reasonably be justified.

"Proterozoic" - the era of geological time between 2.5x109 and 570x106 years ago.

"Proved Ore Reserve or Proven Mineral Reserve" - means the economically mineable part of a measured mineral resource. It includes diluting materials and allowances for losses that may occur when the material is mined. Appropriate assessments and studies have been carried out, and include consideration of and modification by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. These assessments demonstrate at the time of reporting that extraction could reasonably be justified.

"Rehabilitation" - the return of a disturbed area to its original state, or as close as possible to this state.

"Remediation" - to assist in the rehabilitation process by enhancing the quality of an area through specific actions to improve especially bio-physical site conditions.

"Reserve" - that part of a Resource that can be mined at a profit under reasonably expected economic conditions.

"Resource" - mineralized body for which there is sufficient sampling information and geological understanding to outline a deposit of potential economic merit.

"Sandstone" - clastic sedimentary rock with more than 25% clasts of sand.

"Sedimentary" - rocks formed by the accumulation of sediments, formed by the erosion of other rocks.

"Shale" - argillaceous rock with closely spaced, well-defined laminae.

"Sub-outcrop" - rock unit exposure below the surface.

"Sulphide" - a mineral in which the element sulphur is in combination with one or more metallic elements.

"Stratigraphy" - the study of stratified rocks in terms of time and space.

"Tailings" - the waste products resulting from the processing of ore material.