The fundamental consideration in cut-off grade determination is the trade-off between present and future price levels. In addition hedging activities rely on futures contracts. Hence a natural framework to account for these two considerations is a forward curve pricing model.
When gold ore has a high grade, it takes relatively less effort to extract an ounce of gold from the ground; less ore has to be dug out, which reduces input costs for the gold mining company.
If cut-off grade is set too low, then there is overcapacity and equipment meant for a 40,000 tonne a day mine, is expensively underused at 20,000 tonnes a day. Moreover, mines are expected to last a certain number of years, to pay off their capital costs, and return capital to shareholders.
The cut-off grade used by most mining companies for the 'process/do not process' decision, rightly or wrongly, is the break-even cut-off grade. The break-even grade is defined as the grade at which revenue obtained is equal to the cost of producing that revenue.
CHAPTER 8 Stripping Ratios, Pit Limits & Cutoff Grade Optimization Dr. Teuku Andika R Putra USM 2014 Stripping Ratios The stripping ratio (SR) refers to the amount of waste that must be removed for a given quantity of ore in open pit mining.
This means knowing the costs and practicalities of mining and processing for a particular product. A cut-off grade (COG) is an industry-accepted standard expression used to determine what part of a mineral deposit to include in a mineral resource estimate (MRE).
If you increase the cut-off grade, you decrease the life of the mine due to diminishing reserves (reserves are ore in a deposit that is economical to extract, see Mining 101: It's Not that Simple), but you would increase gold production due to the higher grade.
net value after mining i.e. is above the "marginal cut-off grade" (which is the point where the net revenue value of the metal recovered is equal to the cost of processing it). The illustration used throughout involves an ore body with a marginal cut of grade of 1.0%,
Break-even is broken. ... The cut-off grade that is used by most mining companies for the "process" / "do not process" decision, rightly or wrongly, is the break-even cut-off grade.
Output in some mining operations may be limited by capacity in one of the three stages, mining, processing or marketing and could affect the economic cut-off grade.
face of variations of the cut-off grade. The grade tonnage curve is usually calculated with the in-situ resources or reserves and shows always the 'best' or 'optimistic' scenario, i.e., at a given cut-off grade the respective
In this method, the deposit or a portion of it under study is divided into "decision units" based on the mining method and sample data. The statistical grade distribution and the grade-tonnage relationship of each decision unit are then computed based on the samples falling in the unit.
textbooks on geostatistics and cutoff grade estimation. HeisanelectedmemberoftheU.S.NationalAcademyof ... PROCESSING CAPACITY AND CUTOFF GRADE WHEN MINING CAPACITY IS FIXED MINING AND PROCESSING CAPACITY AND CUTOFF ... Examples also show the relationship between cut-off grades and the design of pushbacks in open pit …
definition (cut-off grade determination), ore access mechanics (shaft location, pit size), ... Modern strategic mine planning, a new research initiative at the Colorado School ... from open pit to underground mining, and the placement of shafts. As with financial
An Introduction to Cut-off Grade Estimation includes dozens of charts, graphs, and mathematical formulas to explain basic concepts in a simple, step-by-step fashion. It is a "must read" for mine managers, analysts, geologists, mining engineers, and public policymakers who want to stay on the leading edge of their profession.
The choice of the cutoff grade in mining. Author links open overlay panel Robert D. Cairns a ... The factor β is strongly implicated in extending findings concerning the rate of change of the cut-off grade and the rate of growth of price net of the interest rate. Previous research has also found that the two variables have effects that are ...
on geostatistics and cut-off grade estimation. He is an elect-ed member of the U.S. National Academy of Engineering, a Fellow of AusIMM and SAIMM and a Registered Mem-ber of SME. He was recognised by SME as a Distinguished ... Cut-off grade when mining capacity is fixed
significant economic parameter in mining. Cut-off grade optimization in open-pit mining has been the subject of much research, but more work is needed if it is to cover all essential practical mining considerations. The original algorithm introduced by Lane (1964), which has been applied frequently, is
Cutoff grade, in mining, the level of mineral in an ore below which it is not economically feasible to mine it Cutoff voltage, the voltage at which a battery is considered fully discharged Fuse (electrical), a type of overcurrent protection device
For conducting a mining project's break even analysis, you first need to know about the operational expenses (OPEX).When the OPEX is known, you can calculate the mineral's cut off grade, which is the break even grade, below which it is not economically viable to mine the ore.To find out how I come up with the cost price per tonne (OPEX) if a feasibility study isn't available, I refer you ...
The world's highest grade gold mines ... unit weight of extracted metal making high-grade ore deposits a crucial consideration for all types of investors in mining. The grade of metal in ore ...
The resulting cut-off windows based program is a user-friendly tool which calculates interactively different mining cutoff grade scenarios. The benefits of the methodology are demonstrated using a hypothetical case study.
determination of cut-off grade in mine mining involves complex analysis and scientific calculation, which is tightly related to economic management, ore dressing, mining, geology, applied mathematics and computer knowledge subjects. Taylor[1, 2] presents one of the best definitions of cut-off grade.
May 12, 2006· A cut off grade defines what you will mine for a profit. It will vary for every mineral, for every location, and reflect geological conditions and prevailing metals prices. For example, you can mine surface gold grading much less than a gram per tonne and make a profit, but you would not touch 2 grams per tonne a few kilometres down because it ...
As opposed to the mining cut-off grade that takes the orebody model (Fig. 2(a)) as the geological input, this processing cut-off grade considers the grade-tonnage distribution/curve of the deposit (Fig. 3) within the ultimate pit limit and deﬁnes the cut-off
A gold equivalent cut-off grade of 0.005 oz/ton was used for quartz latite and a cut-off grade of 0.006 oz/ton was used for all other rock types. Cut-off grade was varied to reflect differences in estimated metal recoveries for the different rock types mined.
Cut-Off grade is the minimum grade required in order for a mineral or metal to be economically mined (or processed). Material found to be above this grade is considered to be ore, while material below this grade is considered to be waste.. The cut-off grade can be determined through a variety of methods, each of varying complexity.
This article about how to calculate the cut off grade is a great resource for investors in individual mining stocks. However, when you are investing in mining stocks through a Stock Based mineral ETF I recommend you to read this article too.
Determination of optimal cut-off grade policy to optimize NPV using a new approach with optimization factor. ... A. Mining cut-off grade strategy to optimise NPV based.
Chapter 32 The Determination of a Dynamic Cut-Off Grade for the Mining Industry P. V. Johnson, G. W. Evatt, P. W. Duck and S. D. Howell Abstract Prior to extraction from a mine, a pit is usually divided up into 3-D
The model developed by Lane describes the theory of cut-off grades optimization as well as its effects on the mine planning in an open pit mine (Lane., 1964(Lane.,, 1984(Lane.,, 1988).
Cutoff grade optimization can improve both long-term and short-term cash- flows. Cutoff grade optimization is used for simulation of mining/ processing/ stockpiling configurations to determine which configuration yields the maximum economic benefit.