gangue

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gangue

geology

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June 29, 2026

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In geology, gangue refers to the worthless rock or vein material that contains valuable minerals or metals. When ore deposits are mined, the gangue is extracted along with the desired minerals.12

Concentrating mills are used to process mined ore. Here, the ore is crushed into fine particles and then subjected to processes designed to remove the gangue. For example, in flotation separation, sulfide ores are agitated with water and chemicals. The valuable sulfide particles attach to the chemicals and float to the top as a froth, while the gangue sinks to the bottom.3

The ease with which a mineral can be separated from the gangue is a key factor in determining if it's an ore mineral. Processes like magnetic separation, gravity separation, and flotation are used for this purpose.4

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copper processing
Mineral processing
…from the waste materials, or gangue. In cases where the next step is leaching (most frequently in the case of oxide ores), complete liberation of the copper minerals is not always necessary; the ore needs to be crushed and ground only to the extent required to expose the surface of…
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…from the waste materials, or gangue. In cases where the next step is leaching (most frequently in the case of oxide ores), complete liberation of the copper minerals is not always necessary; the ore needs to be crushed and ground only to the extent required to expose the surface of…
Read More

hand tool
Smelting
…(heavy) and earthy matter, or gangue (light); the two may be largely separated by crushing the raw ore and washing away the lighter gangue. The ore proper is a chemical compound of oxides, sulfides, carbonates, hydrates, silicates, and small amounts of impurities such as arsenic and other elements. Smelting
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…(heavy) and earthy matter, or gangue (light); the two may be largely separated by crushing the raw ore and washing away the lighter gangue. The ore proper is a chemical compound of oxides, sulfides, carbonates, hydrates, silicates, and small amounts of impurities such as arsenic and other elements. Smelting
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ore
…that are collectively known as gangue. Generally, the ore and the gangue are mined together—i.e., taken out of the host rock in a mass by either mechanical or manual means. Then the ore is separated from the gangue by various operations known collectively as mineral processing, or ore dressing. The…
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…that are collectively known as gangue. Generally, the ore and the gangue are mined together—i.e., taken out of the host rock in a mass by either mechanical or manual means. Then the ore is separated from the gangue by various operations known collectively as mineral processing, or ore dressing. The…
Read More