What is unit of stripping ratio?

What is unit of stripping ratio?

In surface mining, stripping ratio or strip ratio refers to the amount of waste (or overburden) that must be removed to release a given ore quantity. It is a number or ratio that express how much waste is mined per unit of ore. Whereas in metal mining, stripping ratio is unitless and is expressed as weight/weight.

What is stripping ratio in open pit mining?

1.3 Stripping ratio The parameter known as the stripping ratio represents the amount of uneconomic material that must be removed to uncover one unit of ore, i.e., the ratio of the number of tons of waste material removed to the number of tons of ore removed.

What is incremental stripping ratio?

Instantaneous (incremental) stripping ratio Instantaneous stripping ratio (SRi) is determined for each bench cut or each cut back (push back). This is purely a physical ratio of waste to ore per bench. [Note: Equation 1 is expressed in tonnes (t), can also be expressed in volume (m3)]

What is instantaneous stripping ratio?

The Instantaneous Stripping Ratio (ISR) is the stripping ratio for a given push back, where a tiny slice of material, i.e., ore and/or waste, is removed from a pit wall. The over-lying waste, i.e., the non-mineral-bearing rock must be removed to uncover and mine the ore.

What is a stripping cost?

Stripping costs are those costs incurred when removing overburden or waste materials in order to obtain access to a commercially-producible ore body. When stripping costs are incurred during the production phase, the firm should treat these costs as variable production costs.

What does pre stripping mean?

Pre-strip by definition is the removal of any waste material not considered to be valuable.

What is deferred stripping cost?

Publication date: 17 Apr 2009. ie. Stripping costs incurred during the development phase of a mine, often referred to as overburden removal costs, are usually capitalised as part of the depreciable cost of building, developing and constructing the mine.

What are stripping costs?

What is stripping activity asset?

A stripping activity asset is depreciated or amortised on a systematic basis, over the expected useful life of the identified component of the ore body that becomes more accessible as a result of the stripping activity. The units of production method is used unless another method is more appropriate.

How is the strip ratio of an overburden calculated?

At their most basic, strip ratios can be calculated by dividing overburden thickness by ore thickness. For example, an overburden thickness of 100 meters and an ore thickness of 50 meters would yield a strip ratio of 2:1.

Why is it important to know the strip ratio?

For instance, a project with a very high strip ratio likely will not be profitable. That’s because a high strip ratio means that the unwanted material is much greater than the amount of ore that can potentially be extracted, making it too expensive to mine.

What should strip ratio be for copper porphyry?

“In the case of a ‘typical’ large (low-grade) copper porphyry deposit, a strip ratio below 3:1 is generally considered good,” Ioannou said. What’s Ahead For Base Metals In 2021?

What is strip ratio of Bisha copper mine?

According to Ioannou, “it is [also] not unusual to see a high-grade volcanogenic massive sulfide base metals deposit support a strip ratio greater than 5:1.” For example, Nevsun Resources’ (TSX: NSU ,NYSEAMERICAN:NSU) high-grade Bisha copper mine in Eritrea posted a strip ratio of 5.4:1 in 2014.