ORE MINERALS
ORE MINERALS
Minerals have been extracted from the earth since prehistoric times and the history of civilization and industrial advancement has been linked with man’s ability to harness and use the minerals available. Once a mineral deposit has been found it has to be extracted from the ground to access the valuable minerals it contains.
REAM SEM OR ORE
It is a natural rock or sediment containing one or more valuable mineral
It is a metalliferous mineral, or aggregate of metalliferous minerals and gangue (associated rock of no economic value), that can be mined at a profit
MINERAL ORES
EXAMPLES OF ROCK DEPOSITS THAT CONTAIN MINERALS
gold, gem, sulfide, carbonate, silicate, aggregate, copper, iron, galena, sand & soil
MINERALS AND ORE DEPOSIT
MINERAL DEPOSIT - designates a natural occurrence of a usual mineral. It is a “geologic term”
ORE DEPOSIT - denotes a mineral deposit of sufficient extent and concentration to invite exploitation. It is an “economic term”
MINERAL EXPLORATION - a complete sequence of activities which aims to discover deposits of minerals and rocks that can be used to meet the resource needs of society
PROJECT DESIGN - this is the initial stage in formulating a project; involves review of all available data (geological reports, mining history, maps, etc.), government requirements in acquiring the project, review of social, environmental, political, and economic acceptability of the project, and budget and organization proposals
FIELD EXPLORATION - this involves physical activities in the selected project area. This can be subdivided into three (3) parts:
REGIONAL RECONAISSANCE - The main objective is to identify targets or interesting mineralized zones covering a relatively large area (regional)
DETAILED EXPLORATION - This involves more detailed surface and subsurface activities with the objective of finding and delineating targets or mineralized zones
PROSPECT EVALUATION - The main objective is to assess market profitability by (1) extensive resource, geotechnical and engineering drilling (2) metallurgical testing and (3) environmental and societal cost assessment.
PRE - PRODUCTION FEASIBILITY STUDY - The feasibility study determines and validates the accuracy of all data and information collected from the different stages; the purpose is for independent assessors to satisfy interested investors to raise funds and bring the project into production
HISTORY OF MINING - archeological discoveries indicate that mining was conducted in prehistoric times
FLINT - the first mineral used. It is because of its conchoidal fracturing pattern, could be broken into sharp - edged pieces that were useful as scrapers, knives, and arrowheads
MINING
It is the process of mineral extraction from a rock seam or ore
It is the process of extracting useful minerals from the surface of the Earth, including the seas
TYPES OF MINING
TWO (2) MAIN METHODS OF MINING
SURFACE MINING
OPEN - PIT MINING
DREDGING
STRIP MINING
QUARRYING
PLACER MINING
UNDERGROUND MINING
TYPES OF MINING
SURFACE MINING - Utilized to extract ore minerals that are close to Earth's surface. There are different types which includes:
OPEN - PIT MINIG - It is the most common. It means a big hole (or pit) in the ground. The pit in mine is created by blasting with explosives and drilling. It is used to mine gravel and sand and even rock.
DREDGING - It is the process of mining materials from the bottom of a body of water, including rivers, lakes, and oceans.
STRIP MINING - It involves the removal of a thin strip of overburden (earth or soil) above a desired deposit, dumping the removed overburden behind the deposit, extracting the desired deposit, creating a second, parallel strip in the same manner, and depositing the waste materials from that second (new) strip onto the first strip.
PLACER MINING - It is mining of stream bed (alluvial) deposits for minerals. This may be done by open-pit or by various surface excavating tunneling equipment
UNDERGROUND MINING - Utilized to extract ore minerals from the orebody is that is deep under the Earth's surface.
MILLING OR MINERAL PROCESSING
It is the process of extracting minerals from the ore, refining them, and preparing these minerals for use.
It is an art of treating crude ores and mineral products in order to separate the valuable minerals from the waste rock, or gangue
MILLING ORMINERAL PROCESSING
PRIMARY STEPS IN PROCESSING MINERALS
SAMPLING - the removal of a portion which represents a whole needed for the analysis of this material.
ANALYSIS - is important to evaluate the valuable component in an ore. This includes chemical, mineral and particle size analysis.
COMMUNICATION - is the process where the valuable components of the ore are separated through crushing and grinding.
CONCENTRATION - involves the separation of the valuable minerals from the raw materials
DEWATERING - this involve filtration and sedimentation of the suspension and drying of the solid materials harvested from this suspension.
EXAMPLES OF MINING OR RECOVERY METHODS OR PROCESSES
HEAVY MEDIA SEPERATION - the crushed rocks are submerged in liquid where the heavier/denser minerals sink thus are separated from the lighter minerals.
MAGNETIC SEPERATION - if the metal or mineral is magnetic, the crushed ore is separated from the waste materials using a powerful magnet.
FLOATATION - the powdered ore is placed into an agitated and frothy slurry where some minerals and metals based on physical and chemical properties may either sink to the bottom or may stick to the bubbles and rise to the top thus separating the minerals and metals from the waste.
CYANIDE HEAP LEACHING - this method used for low-grade gold ore where the crushed rock is placed on a "leach pile" where cyanide solution is sprayed or dripped on top of the pile.