Ore Minerals Lecture Notes PDF

ORE MINERALS LECTURE NOTES Ore- is a rock that contains concentra:on of valuable minerals. These are naturally occurring and it can also be a mineral, metal, or non-metallic materials that can be profitably mined. An o...

ORE MINERALS LECTURE NOTES Ore- is a rock that contains concentra:on of valuable minerals. These are naturally occurring and it can also be a mineral, metal, or non-metallic materials that can be profitably mined. An ore is iden:fied according to its overall chemical composi:on, percentage of extractable resource, market value. The bauxite is a rock that contains minerals that are used to make aluminum. Mining - extrac:on of valuable minerals and other materials from the ground. FOUR STAGES: ❖ > Explora:on ❖ > Development and Construc:on ❖ > Commercial Opera:on ❖ > Rehabilita:on Mineral Explora6on 💎 is a range of ac:vi:es to help determine if there are minerals under the ground; This is a process of searching for evidence of any mineraliza:on hosted in the surrounding rocks; If the explora:on process iden:fies minerals can be commercially extracted, then mining in the future may be possible. It is very rare to find sufficiently enriched ore bodies, most explora:on campaigns stop aNer the first/couple of stages. In fact, Less than one per cent of explora:on projects typically progress to establishing a mine. This is part of the reason why mining and the resources extracted come at a high financial cost. The likelihood of explora:on ac:vity leading to a mine is very low. Apart from the size and quality of the mineral deposit iden6fied through explora:on, a range of other factors will determine the commercial viability of a project, such as establishment and produc6on costs, commodity prices, transport costs, interna6onal supply compe66on and demand, as well as exchange rates. Mines are subject to planning approval and strong regulatory controls. I. Early Stage Explora:on - once an explorer has obtained minerals explora:on license, field explora:on starts. *Mineral explorers (also called Prospectors) oNen use planes or helicopters to view large areas efficiently; prospectors look in the rocks for useful minerals and other clues to where a deposit may be hidden. Explorers take measurements through surveying, some:mes using magne:c or electrical instruments. The goal of the prospec6ng stage is to find the clue that there is something much bigger beneath the surface. a. aerial surveying b. ground mapping d. geophysics c. geochemistry -rock sampling -water tes:ng -soil tes:ng Outcrops and showings provide prospectors with visible bedrock and allows some ini:al geological sampling, analysis and interpreta:on. Indicator minerals are minerals found at the surface that may indicate the presence of valuable ore underground. In the search for minerals, prospectors and geoscien:sts explore large areas on foot, iden:fying and mapping loca:ons they have visited, taking small samples of rocks, soils, water, and some:mes vegeta:on, to be analyzed for clues that could lead to the discovery of a deposit of useful minerals. Advanced technologies via aerial surveys can mean explorers do not need to access private property at all 2. Late Stage Explora:on- drilling- “truth machine” As the explorer learns more about the geology, the explora:on program progressively focuses on much smaller areas, or targets, within the minerals license boundary. Explorers may adopt more specific directed explora:on techniques, such as drilling to sample rock at different depths below the surface. Drilling is expensive and is used selec6vely. Ini:al drilling involves taking samples through a small hole – usually less than 100 mm in diameter – through soil and loose rock. This tells the geologist what types of rock exist under the surface and if minerals are present. If minerals are iden:fied, explorers may drill deeper holes, oNen using diamond drills to cut through hard rock. Through this process the geologist can determine how much mineral is present and give an indica:on of whether minerals may occur in economic quan::es. At this stage, bulk samples may also be taken. Development and Construc:on DEVELOPMENT -Building roads Processing facili:es-crushing and processing facility is constructed based on the tes:ng, Employee housing- workforce accommoda:on Maintenance facili:es - loca:on for service and repair of mine equipment to reduce down:me and ensure that produc:on capacity and safety objec:ves are met. Management offices, workshops, storage, refuelling, and power genera:on facili:es. In some cases, a control tower may also be constructed to offer a complete view of processing opera:ons. Transporta:on for mine personnel - Miners, contractors, and supervisors need to move between work areas which may be spread across a wide area. Surface Mining Ø preference for mining companies. Ø considered safer Ø doesn’t require extensive electricity rigging and water piping. ****Surface mining is oNen the preference for mining companies. This is by removing the terrain surface, or overburden, to access the mineral beneath is oNen more cost-effec6ve than gouging tunnels and subterranean shaNs to access minerals underground. This method is oNen considered safer, as well, and doesn’t require extensive electricity rigging and water piping. Strip mining- Coal and Lignite (brown coal) are the two Principal minerals that are extracted through this method. This process involves dividing into two, area stripping and contour stripping. This method of striping is common on flat land to extract the mineral over a large area. Open-pit mining is a method in which an ore is removed by digging a pit in the ground, used to remove copper, gold, iron, as well as non-metallic minerals. It is normally used when the rock layer above the ore is too weak to allow underground tunnels. In this technique, circular steps, or 'benches', are dug around the circumference of the pit to remove ore from the sides. ****When ore can no longer be removed from one bench, a new one is dug at a lower level. Thus, open-pit mining is ideal for ore deposits lying under thin rock, or ore deposits in the form of layers which can be easily removed by digging benches. The equipment used for this method is mostly restricted to dump or haul trucks, and shovels, though conveyors can quicken the process. ****Many accidents occur when the mine props collapse due to earth tremors. Explosions, too, trigger casual:es when ven:la:on systems fail to effec:vely remove exhaust from mining equipment, coal dust and natural underground gas leaks. Blas:ng can ignite those gases, leading to deaths from both the explosions themselves and the subsequent collapse of mine structures Underground Mining ROOM AND PILLAR method otherwise known as the con6nuous mining. This is one of the safest and the oldest methods of mining.. It is efficient and eco-friendly too. As the name indicates it is a method by which the large pillars of coal are leV standing to support the room of the mine. PILLAR-VERTICAL STRUCTURE. Commercial Opera:on ❖ * produc:on of commercial quan::es How do you separate the valuable materials? Density Separa:on: Panning One of the first methods for mining gold was that of panning, a technique where ore is mixed with water and forms a suspension. When it is shaken, the dense par:cles of gold sink to the bodom and could be removed. Floata:on Flota:on makes use of density separa:on, but in a special way. Chemicals are added to change the surface proper:es of the valuable minerals so that air bubbles can adach to them. The minerals are mixed with water to make a slurry, almost like a watery mud. Air bubbles are blown through the slurry and the minerals adach to the bubbles. The air bubbles are much less dense than the solu:on and rise to the top where the minerals can be scraped off easily. Magne:c Separa:on Rehabilita:on ❖ Before the company can be issued a permit to build the mine, they must first prove that they have the funds and plans to close the mine in a safe and structured way. ❖ Ensuring public health and safety ❖ Removing waste and hazardous material ❖ Establishing new landforms and vegeta:on ANer the mining is finished, the land is greatly disturbed. The area around the mine needs to be restored to its natural state. This process of restoring the area is called “reclama:on.“ Na:ve plants are planted. Pit mines may be refilled or reshaped so that they can become natural areas again. The mining company may be allowed to fill the pit with water to create a lake. The pits may be turned into landfills. Underground mines may be sealed off or leN open as homes for bats. Masbate Gold Project a gold mining company in Barangay Puro, Aroroy in the Province of Masbate showed that responsible mining can be done. It started progressive rehabilita:on in January 2012. The Masbate Gold Project has three (3) rehabilitated areas being maintained: the Colorado Waste Dump; the Syndicate Waste Dump; and Holy Moses Basalt (HMBE) Stage 4 Waste Dump. QUEZON, Nueva Vizcaya: A Bri:sh mining company has succeeded in its rehabilita:on project with more than 3.6 million trees planted in 600 hectares of land in this province. ****Mining provides people with many resources they need, but mining can be hazardous to people and the environment. Miners should restore the mined region to its natural state. It is also important to use mineral resources wisely. Most ores are non-renewable resources.