INDUSTRIAL MINERAL MINING: MARBLE

Marble is a white colour calcitic lime stone.

It a stone with  glaring and decorative texture.

It has coarse texture with dominantly calcite Mineral. Marble has white streak but varies in colour from pure white, off white, Ash depending on it formation.It color also depends on the following:

Primary rock from which it formed, composition, degree of weathering process it has undergone, type of metamorphism it undergone (contact or regional) among others. Marble is a monomineralitic rock..

Marble is a carbonate rock, it has hardness of 3 on mohr's scale of hardness.

"Marble More of Formation" 

Marble bus formed through metamorphosim process. When Argillaceous grain limestone undergone metamorphosim under high temperature, it undergone recrystallization which led to the formation of Marble. As existing limestone formation is heat up by intrusive magma it grains undergo Reformation.. Marble is an industrial  rock as it a useful industrial material.

Marble as one of the useful industrial raw material can be mined as aggregate and also can be extracted as dimension block. Marble as a competent rock of compressive strength greater than 35Mpa can be mine by Quarry Mining method, Open pit and other applicable methods depending on the formation orientation, dimension (size&shape), overburden thickness.

Marble aggregate is mine using drilling and blasting to break the marble deposit into handable sizes. 

This method involved the following operation sequentially:

Development operation, Drilling, Blasting, loading and hauling, Processing.

The following documents are required to apply for a Mineral title; Exploration Report, Minimum work program report (MWP) Environmental impact Assessment (EIA), Community Agreement signed by necessary community leaders, evidence of compensation to the land owner and previous land users. Have once explain each of this documents once. In case you want to write or learn how to write you can reach me, I will put you through @Giant Miner training stope.

After acquiring the deposit, development operation start by road creation and land clearing to give a work space allowance where mining can start proper. Development operation: The first thing before any mining operation can commence is to acquire the deposit both as mandated by Mining Act and Regulations. After exploring the deposit, necessary mapping operation to understand formation orientation and dimension is carryout. This is operation is follow by core drilling operation to know both quantity and quality of the formation. All this operation is done under Exploration License (EL). This license is renewable and  can be extend on additional Mineral. After exploration process, Exploration Report is submitted to the ministry of mine office along side with other documents for Mining license processing. After successful Blasting, marble aggregate is load and haul for milling.

Uses of marble aggregate includes; for animal feed production, paint production, cement production, iron ore pyrometallurgical processing in blast furnace, tooth paste and pharmaceutical industrial use, construction purpose, uso as drilling mud addictive among other uses. The marble Run-off-mine is milled into fine product or hammer milled.

After drilling operation which is assumed to be as planned and design in alignment with the mine design.

Blasting operation is done by loading the drill holes with specified quantity of explosive. In open pit the deposit is work in benches, why in Quarry it's worked in a single bench. For the first Blasting operation, box cut Blasting design is use for the creation of additional free face. In the box cut design, inner holes are initiated first then preceeded by the following ones. Th inner hole create a crater which create horizontal Free face. The crater geometry depends on the depth of burial of Explosive and other parameters in place.

Drilling and Blasting operation commence after the deposit has been developed. For both open pit and Quarrying, the overburden material removed from the deposit is stockpile in a remote area where it's kept for reclamation. All operation on this marble deposit must be done as proposed in the minimum work program report (MWP). Drilling as we all know is the creation of cavity into the marble formation for the placement of Explosive. The development operation can b done using Excavator machine, payloader and other mine machineries. Most time when the area to dump marble overburden is far, dump trucks and other haul trucks can be used  Reason why Marble is as useful as it's

Marble compose of calcite (CaCO3). Calcite is a Mineral of high cementric property and it's rich in calcium. Calcite find it use in cement company due to it cementing property and ability to glue. During Diagenesis process of sedimentary rock formations, calcite play the role of cementing sediments together after lithification and dewatering process. This calcite of plane cleavage and two dimensional cleavage plane is said to be formation from the remain of past sea creatures. High calcium content in marble makes it useful for pharmaceutical industry. Marble dimension block Extraction:

Apart from mining marble as aggregate it can be cut into slabs and polish into chair, table and tiles among other things. Marble as a source of calcium is also use for animal feed (pig meal and poultry meal). Marble is use for iron ore process as a reactant to remove hematite (Fe2O3)  oxygen as CaCO3 need more oxide to burn off its carbonate so as to produce quick lime.

When calcite is heated at high temperature, the carbonate content combust and burn off to produce quick lime. When hydrated produce hydrated lime which is a raw material for water purification and other uses. Marble aggregate is useful as an industrial material. 

Marble Dimension block Extraction

Dimension stone Quarrying is another aspect of mining that involves the cutting of rock mass into block which is to be polish into different ornamenal finish goods including chair, table, stool, tiles among other. 

Slab cutting techniques of marble extraction involve creating face for dimension block and detachment of the cut block from the insitu rock. This extraction begins from site mapping to check the formation competency. For a marble formation to be competent for dimension block cutting it must be of; discontinuity and crack free, low water absorption, low porosity, moderate strength among other characteristics. Availability of fracture in rock mass render the formation useless as dimension block material. Existing fractures in marble rock mass (joint, fault, and others fissures) makes it difficult to extract block as they tends to break into chippings and undimensional boulders. High strengtharble formation containing metallic minerals and hard grains affect the cutting tools and it cutting efficiency. Therefore before establishing a dimension block cutting Quarry, the following properties of the formation must be justify with the international Rock Mechanics standard.

Properties to be test for includes but not limited to:

1. Rock Uniaxial compressive strength UCs

2. Porosity

3. Water absorption rate

4. Durability

5. Discontinuity mapping

6. Petrographic check for aesthetic appearance.

7. And others

Marble Dimension stone cutting can be done using cutting machine, drilling and blasting, usebof soundless demolition Chemical Agent and presplitting.