GEOLOGY HUB Latest Questions
What is room and pillar mining?
What is room and pillar mining?
Read lessWhat is placer deposit? How placer deposits are formed
What is placer deposit? How placer deposits are formed
Read lessTypes of Blasting 1. Abrasive blasting 🔹vombines a pressurized stream of air with an abrasive, which is propelled onto the surface of steel to remove paint, rust, and contaminants. 🔹Abrasive blasting can also be used on concrete to remove discoloration and other marks, ...Read more
Types of Blasting
1. Abrasive blasting
🔹vombines a pressurized stream of air with an abrasive, which is propelled onto the surface of steel to remove paint, rust, and contaminants.
🔹Abrasive blasting can also be used on concrete to remove discoloration and other marks, and on brick and masonry to clean it.
🔹Dry abrasives used in surface prep include sand, sand substitutes, coal slag, steel grit and garnet.
🔹Dry abrasives are sometimes combined with a sponge media to reduce dust at the site of the blast, and sponge is recyclable.
2. Vacuum blasting systems
🔹capture and collect the blast media;
3. Water blasting
🔹uses water with abrasive, reducing dust;
4. Bristle blasting
🔹Aand-held power tool that removes contaminants and creates a surface profile using wire belts , typically used for small areas.
5. Shot blasting
🔹typically used on concrete to remove existing coatings, and dirt;
6. High pressure water blasting
🔹water only, at high pressure to clean surfaces and create a profile.
Read less⚒ BASIC CONCEPTS OF DRILLING ⚒ 🔷 The most effective, and hence most usually adopted, method of destruction of an the object is by blasting. 🔷 This method invariably aims at breaking the object into several small pieces. 🔷 Explosives are used for ...Read more
⚒ BASIC CONCEPTS OF DRILLING ⚒
🔷 The most effective, and hence most usually adopted, method of destruction of an the object is by blasting.
🔷 This method invariably aims at breaking the object into several small pieces.
🔷 Explosives are used for the purpose of breaking the object.
🔷 An explosive is a substance that generates a very high volume of gases and a huge quantity of heat within a very short time span of a few milliseconds as soon as it is ignited.
🔷 When gases are generated by ignition in this way, very high pressure is exerted
on the surroundings.
🔷 At the same time, the strength of the surrounding material also reduces considerably due to the heat.
🔷 As a result of this, cracks develop in the material and the material gets fragmented.
🔷 When the place of generation of gases is confined, the gases cannot escape to the atmosphere and the intensity of the pressure increases to a considerably higher level.
🔹 This results in maximum destruction.
For the most effective destruction of surrounding material, a hole is drilled in the material to be destroyed. After completion of drilling, the hole is charged (i.e. filled with explosive material) in a certain predefined manner.
🔷 A detonator, connected by two copper wires, is kept in the hole while the explosive is filled. The hole is then sealed from the top.
🔹Once the appropriateness of all the precautionary measures is verified, an electric current is sent through the wires.
🔹The electric current heats the wire in the detonator and the explosive material in the detonator explodes.
🔹This explosion causes further detonation in the explosive-filled hole. The hole drilled for filling explosives in this manner is called a blast hole.
🔷 The process of drilling such holes is called blasthole drilling.
🔷 The process of drilling such holes is called blast-hole drilling.r often simply a drill.
🔷 Except cases like breaking a boulder in field etc., a blasthole is seldom drilled in the singular.
🔷 They are drilled in numbers, perhaps in hundreds, one after another, then charged and blasted simultaneously.
🔷 The fragmented rock mass formed by blasting is almost always moved away, either to create space, as in civil engineering projects, or to extract a mineral of interest, as in mining or quarrying.
🔷 If the sizes of the fragments are small they can be moved easily.
🔷 In order to have a small size rock fragments after a blast, blast holes are required to be located in a properly planned manner.
🔷This requires careful design to determine the diameter, depth, and inclination of the holes, and also layout and other relevant parameters of the holes.
Read less“Soils Associated with Gold Deposits” 🔶By far, the best-known type of soil which may indicate the presence of gold is known as “black sand.” Let’s know more about it 🔶 Black sands are certainly not proof of the existence of nearby gold, only ...Read more
“Soils Associated with Gold Deposits”
🔶By far, the best-known type of soil which may indicate the presence of gold is known as “black sand.”
Let’s know more about it
🔶 Black sands are certainly not proof of the existence of nearby gold, only that the soil has a lot of minerals and heavy metals, one of which is gold.
🔶 Gold is one of the heaviest substances – about 19 times the weight of water – so any gold being carried by water in a stream is the first to fall.
🔶Black sand is not as heavy as gold, which is more than 3 times as heavy as the iron which makes up much of the black sand, it still weighs more than most other substances. So, while black sand does not guarantee gold, it is definitely worth a look for that elusive treasure.
🔶Changes in the color of soil can be another indicator of nearby gold. Iron staining is another excellent indicator that gold may be present.
🔶The iron stains are in yellow or reddish soil.
🔶Soil which contains iron may also be black, provided it has not oxidized.
Where iron or other heavy metals are located, gold may also be found.
🔶Soil and rocks are sometimes bleached to a lighter color than other nearby rocks due to acid from lode deposits underground.
🔶Sometimes, gold is near that lighter rock and soil.
🔶Contact points between different types of rocks can be another sign that gold may be nearby.
🔶 This very important indicator is often overlooked by prospectors.
🔶 Contact points are usually where different rock types come together at a 90-degree angle.
🔶 The existence of contact between different rock types is often more important the rocks themselves.
🔶When different types of rocks came into contact deep underground, the resulting pressure and very high temperatures due to this pressure caused fissures to develop in the rocks.
🔶 Gold would liquify under this heat and be pushed up toward the surface. Over time, the gold cooled and returned to its solid form.
🔶Thanks to this pressure, gold will now be close enough to the surface for even amateur prospectors to find
🔶Contact points where different types of rocks meet can also sometimes contain stones that are damaged so they crumble easily.
🔶There could be gold in those crumbly rocks. The border between the rock types on the surface could be the key to what lies beneath the surface.
🔶Although gold might be found in many different types of rock, quartz may be the most likely home for gold. Just saying “look for quartz” would be much worse than a waste of time, because it is the second most common substance on the planet.
🔶Although most types of quartz might potentially contain gold, rocks known as “dirty” or “rotten” quartz are much more likely have gold.
🔶Ironically, these rocks might be considered to be the least attractive when looking them.
🔶However, the brown or orange pieces contained in the dirty quartz are oxidized iron pyrite, which is commonly found with gold.
🔶 Perhaps this is the perfect example of not judging a book by its cover – what looks ugly on the surface may be a sign of something truly beautiful underneath.
Read lessMinerals containing elements of economic value are generally present in all igneous rocks, but the elements may not be concentrated enough to make mining economical. Only in relatively rare circumstances are they in sufficient abundance so that mining is profitable. If the ...Read more
Minerals containing elements of economic value are generally present in all igneous rocks, but the elements may not be concentrated enough to make mining economical.
Only in relatively rare circumstances are they in sufficient abundance so that mining is profitable.
If the minerals are scattered throughout a host rock, but in sufficient amounts to mine profitably, we call the deposit a disseminated deposit.
Disseminated deposits produce most of the world’s diamonds, copper, and molybdenum and also large percentages of the available tin, silver, and mercury.
Often, disseminated ores consist of minerals scattered randomly in a host rock.
Sometimes geological processes concentrate ore minerals in vein deposits consisting of veins that are centimeters to meters thick.
If ore is distributed in many small veins, geologists call the deposit a lode deposit. Vein deposits account for most of the world’s gold and silver mines, and also some copper and lead-zinc mines.
In still other kinds of igneous deposits, ore minerals become concentrated in layer
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