In the econometrics of mineral resources, cut-off grades are threshold values used to determine the economic viability of mining operations. The cut-off grade depends on several parameters, and we primarily distinguish between: The geological cut-of grade The geological cut-off grade is employed to generate frequency distributions of grades to separate mineralised materials from waste and […]
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Core barrels: an overview
MarcialWhat is a core barrel? The core barrel is an essential part of each coring practice as it collects the core sample in its inner tube and simultaneously its outer tube acts as the BHA. Core barrels are not all the same, but rather differ and have different features and components depending on the coring […]
Classification of the Drilling Rate Index
MarcialWhat is drilling rate index? DRI is a measure of the difficulty or ease of drilling rock, and it was developed at the Norwegian University of Science and Technology in Trondheim, Norway.ย The DRI value is strongly related to the uniaxial compressive strength and indirect tensile strength. However, when the uniaxial compressive strength and tensile strength […]
Placer deposits
MarcialPlacer deposit are natural concentration of heavy minerals caused by the effect of gravity on moving particles. When heavy, stable minerals are freed from their matrix by weathering processes, they are slowly washed downslope into streams that quickly winnow the lighter matrix. Thus, the heavy minerals become concentrated in stream, beach, and lag (residual) gravels […]
Optimisation of Cut-Off Grade Considering Dilution and Waste Rehabilitation Costs
MarcialA paper written by: Pascal Amedzrovi, George Agyei, University of Mines and Technology, Tarkwa, Ghana. The most important factor in mine production planning is called cut-off grade. Therefore, itโs accuracy is important as it can seriously impact the net present value (NPV). The Laneโs approach is commonly used to determine the optimal cut-off grade by […]
Key informations about Escondida Mine
MarcialLocation At 170 km southeast of Antofagasta, in the northern Chilean Atacama Desert, sits the copper porphyry deposit known as Escondida. In Spanish, the name Escondida means “hidden.” It comes from the primary orebody, which is concealed by hundreds of meters of overburden and does not outcrop on the surface. Ownership The world’s greatest producer […]
General rules for plant design (Part 02)
MarcialYesterday, we present a first rule that guides plant design and surely you noticed that a metallurgist has a huge duty and to reach processing goals, he must work with project geologists. Today, letโs discuss on the second law. What does the second rule say? Second rule: Planning for the estimation of the start-up parameters […]
How does the depth of a deposit affect the cut-off grade?
MarcialA cut-off grade determines which drilling intercepts may and cannot be used in a JORC resource. It is the grade of mineralisation at which a deposit can be exploited profitably. The price at which a firm can sell the underlying commodity and the cost of mining a deposit determine the cut-off grade. The cut-off grade […]
The impact of the circular economy in the mining industry
MarcialMining involves supplying core raw materials to global supply and value chains. Therefore, the mining industry plays an essential role in global economic and social development (Gedam et al., 2021). The transition towards sustainable environmental management is also important because the demand for mining inputs is expected to double by 2030 (Lรธvik et al., 2018). […]
General rules for plant design (Part 01)
MarcialMore than merely the project’s immediate technical and engineering requirements fall under the purview of the metallurgists and engineers designing a new plant. Some of the broader issues that should be considered for your next design job are covered in this blog. What are the rules for efficient plant design? First rule: The most critical […]