Rice. 8. Short cone hydrocyclone

 , E au , C au depend on the material composition of the ore and the form of Au in

 = 0.110 - concentrate yield;

E au - 20  60% - Au extraction;

C au - 20  40 g/t - Au content.

Gravity concentrate is a granular material with a particle size of 13 mm. Its composition:

1. When processing quartz ores - large pieces of quartz SiO 2; Large Au (loose or jacketed), small Au (slightly), Au intergrown with MeS, SiO 2 ;

2. When processing sulfide-quartz ores - MeS sulfides (FeS2, FeAsS, CuFeS2, PbS,...); a small amount of large pieces of SiO 2, large Au, fine Au in intergrowths with sulfides, finely dispersed Au.

Methods for processing gravity concentrates

Example: Figure 9.

In most factories it is subjected to finishing or re-cleaning to obtain the so-called gold head C Au [kg/t] - 10  100. Finishing is carried out on concentration tables or short-cone hydrocyclones.

The resulting Au head can be processed using various methods:

Amalgamation;

Hydrometallurgical.

The most common gold-bearing matrix in the world is quartz veins. I am not a geologist, but a miner, and I know and understand that the geological characteristics of gold-bearing quartz veins very important. These include:

Sulfides and chemical oxidation

Most gold-bearing quartz veins or veinlets contain at least small amounts of sulfide minerals. One of the most common sulfide materials is iron pyrite (FeS 2) - pyrite. Pyrite is a form of iron sulfide that results from the chemical oxidation of some of the inherent iron in the rock.

Quartz veins containing iron sulfides or oxides are quite easy to recognize, since they have a recognizable color - yellow, orange, red. Their "rusty" appearance is very similar to the appearance of rusty oxidized iron.

Host or local rock

Typically (but not always) quartz sulfide veins of this type can be found near major geological faults or in areas where tectonic processes have occurred in the recent past. Quartz veins themselves often "break" in many directions, and quite a lot of gold can be found at their junctions or cracks.

Host rock is the most common type of rock surrounding a vein (including raft) in any location where gold is contained. In areas where quartz veins can be found, the most common host rocks are:

• slate (especially greenstone slate)
• serpentine
• gabbro
• diorite
• siliceous shale
• feldspar
• granite
• greenstone
• various forms of metamorphic (altered) volcanic rocks

The last type deserves special mention. Many people new to gold mining, or those who have little understanding of gold mineralization processes, automatically assume that gold is found in all areas where there is evidence of volcanic activity.

This point of view is wrong! Areas and areas where some volcanic activity has recently (from a geological point of view, of course) rarely boast gold in any concentrations. The term "metamorphic" means that some type of significant chemical and/or geological change occurred over many millions of years, changing the original volcanic host rock into something completely different. By the way, the most gold-rich areas in the American West and Southwest were formed in places characterized by metamorphism.

Shale, limestone and coal

Geologists would say that places where there are host rocks characterized by shale, limestone, or coal content may also contain gold-bearing quartz veins. Yes, there are experts in geology, I respect them, but I will tell you something right here and right now. In 30 years of small-scale gold mining, I have not found an ounce of gold in areas where the above host rock types were found. However, I have been prospecting in New Mexico where you can find rich metamorphic rock within a few miles of rock with limestone, shale and coal. Therefore, geologists would need to resolve this issue.

Related Minerals

Many types of minerals accompany gold-bearing quartz veins and are contained in the surrounding host rock. For this reason, I often talk about the importance of understanding (or simply having the appropriate knowledge) of gold geology and associated mineralization. The key point here is that the more knowledge and experience we have, the more gold you will eventually discover and extract.

This is quite old wisdom, so let's take a look at the associated minerals that are characteristic of gold-bearing quartz ores:

1. Natural gold (that's what it's all about, right?)
2. Pyrite (our good old iron pyrite)
3. Arsenopyrite (arsenic pyrite)
4. Galena (lead sulfide - the most common form of lead ore)
5. Sphalerite (a type of zinc ore)
6. Chalcopyrite (copper pyrite)
7. Pyrrhotite (an unusual and rare iron mineral)
8. Telluride (a type of ore, often refractory; meaning that the precious metal it contains is usually in a chemical form and cannot be easily crushed)
9. Scheelite (main type of tungsten ore)
10. Bismuth (has characteristics similar to antimony and arsenic)
11. Cosalite (lead and bismuth sulfide, found with gold, but more often with silver)
12. Tetrahedrite (copper and antimony sulfide)
13. Stibnite (antimony sulfide)
14. Molybdenite (molybdenum sulfide, similar in appearance to graphite)
15. Gersdorfit (mineral containing nickel and arsenic sulfide)

Those attentive may have noticed that I did not include in this list the designations adopted in the Periodic Table of Elements and mineral formulas. If you are a geologist or a chemist, then this would be mandatory for you, but for a simple gold miner or prospector intending to find gold, from a practical point of view, this is not necessary.

Now I want you to stop and think. If you can identify all of these minerals right now, will this ability increase your chances of success? Especially in discovering potential gold deposits or establishing the fact of high mineralization of a particular area? I think you get some of the big picture.

Quartz Ore

Quartz Ore ID: 153 .

NID: quartz_ore.

Nether quartz ore in Minecraft is also called: Nether Quartz Ore, Nether Quartz Ore, Quartz Ore.

How to get:

Quartz ore in Minecraft, which is sometimes called differently, although the essence does not change, is the only ore that can only be found in Hell (in the Nether). Moreover, there are only two ores - quartz and emerald, which are generated in separate biomes. Nether ore is quite explosion-resistant and cannot burn forever, which is different from hellstone (netzerite). And you can break it with any pickaxe. Now everything is in order and a little more detailed.

Where can I find quartz ore in Minecraft and how to mine it?

“He who has not seen hell will not be pleased in heaven” (Lezgin proverb).

So, Quartz Ore is found in the Nether, where its abundance is similar to Iron Ore, and forms in veins 4-10, just like Iron Ore.

When quartz ore is destroyed with any pickaxe, 1 quartz will fall out. As with many Minecraft ores, mining quartz ore results in an object. That is, in order to mine the block itself, you will need a pickaxe with “Silk Touch”. If you use a pickaxe enchanted with Luck, the amount of quartz mined from an ore block can be increased to four.

What can be made from quartz ore

"A little deed is better than a lot of idleness."

In order to make quartz in Minecraft, you need to burn quartz ore in a furnace using any fuel. And then quartz can be used as a crafting ingredient in crafting recipes:

• observer,
• comparator,
• daylight sensor,

From gold ores various types quartz ones are the simplest in terms of technology. In modern extraction plants that process such ores, the main process for extracting gold is mixing. However, in most cases, quartz ores, in addition to fine gold, also contain significant and sometimes predominant amounts of large gold, which slowly dissolves in cyanide solutions, as a result of which gold recovery during cyanidation is reduced. In these cases, in technological scheme factories include the operation of extracting large gold using gravity enrichment methods.

Gravity enrichment tailings containing fines are subjected to cyanidation. This combined scheme is the most versatile and, as a rule, provides high gold recovery.

In many domestic and foreign factories, gold-bearing quartz ores are crushed in circulating cyanide solutions. When working according to this scheme, the main amount of degold solution obtained as a result of gold deposition with zinc is sent to the grinding cycle and only a small part of it is sent to neutralization and to the dump. Discarding part of the gold-free solution prevents excessive accumulation of impurities in it, which complicate the process. The more impurities that go into the solution, the greater the proportion of the discharged solution.

When grinding in a cyanide solution, most of the gold (up to 40-60%) is leached during the grinding process. This makes it possible to significantly reduce the duration of subsequent cyanidation in agitators, as well as reduce the consumption of cyanide and lime by returning part of these reagents to the process with gold-free solutions. At the same time, the volume of wastewater is sharply reduced, which leads to a reduction in the cost of its disposal and virtually eliminates (or sharply reduces) the discharge of tailings into natural water bodies. The consumption of fresh water is also reduced. However, grinding in a cyanide solution also has its disadvantages. The main one is the sometimes observed decrease in gold recovery, which is mainly due to the fatigue of cyanide solutions due to the accumulation of impurities in them.

Other disadvantages include the large volume of solutions sent for gold precipitation and the circulation of large masses of cyanide gold-containing solutions between operations. The latter circumstance creates the danger of additional losses of gold (due to leaks and overflows of solutions) and complicates the sanitary situation at the factory. Therefore, the question of the advisability of grinding in a cyanide solution is decided individually in each specific case.

In some cases, it is carried out in two or three stages, separating the solutions from the solid phase after each by condensation or filtration. This technique provides higher gold recovery due to reduced fatigue of cyanide solutions.

When processing quartz ores using sorption technology, coarse ores are also extracted using gravity enrichment methods.

You are reading an article on the topic Quartz gold ores

Quartz- one of the most common minerals in the earth's crust, a rock-forming mineral in most igneous and metamorphic rocks. Free content in the earth's crust is 12%. It is part of other minerals in the form of mixtures and silicates. In total, the mass fraction of quartz in the earth's crust is more than 60%. It has many varieties and, like no other mineral, is varied in color, in forms of occurrence, and in genesis. Found in almost all types of deposits.
Chemical formula: SiO 2 (silicon dioxide).

STRUCTURE

Trigonal system. Silica, the most common form of which in nature is quartz, has developed polymorphism.
Two main polymorphic crystalline modifications of silicon dioxide: hexagonal β-quartz, stable at a pressure of 1 atm. (or 100 kN/m2) in the temperature range 870-573°C, and trigonal α-quartz, stable at temperatures below 573°C. It is α-quartz that is widespread in nature; this modification, stable at low temperatures, is usually called simply quartz. All hexagonal quartz crystals found under ordinary conditions are paramorphoses of α-quartz over β-quartz. α-quartz crystallizes in the class of trigonal trapezohedron of the trigonal system. The crystal structure is of a frame type, built from silicon-oxygen tetrahedra arranged in a helical manner (with a right or left turn of the screw) relative to the main axis of the crystal. Depending on this, right and left structural and morphological forms of quartz crystals are distinguished, distinguishable externally by the symmetry of the arrangement of some faces (for example, trapezohedron, etc.). The absence of planes and a center of symmetry in α-quartz crystals determines the presence of piezoelectric and pyroelectric properties.

PROPERTIES

IN pure form Quartz is colorless or white due to internal cracks and crystalline defects. Impurity elements and microscopic inclusions of other minerals, mainly iron oxides, give it a wide variety of colors. The reasons for the color of some varieties of quartz have their own specific nature.
Often forms doubles. Dissolves in hydrofluoric acid and alkali melts. Melting point 1713-1728 °C (due to the high viscosity of the melt, determining the melting point is difficult; there are different data). Dielectric and piezoelectric.

It belongs to the group of glass-forming oxides, that is, it can be the main component of glass. One-component quartz glass made from pure silicon oxide is obtained by melting rock crystal, vein quartz and quartz sand. Silicon dioxide has polymorphism. A polymorphic modification that is stable under normal conditions is α-quartz (low temperature). Accordingly, β-quartz is called a high-temperature modification.

MORPHOLOGY

Crystals are usually in the form of a hexagonal prism, topped at one end (less often at both) with a six- or three-sided pyramidal head. Often, towards the head, the crystal gradually narrows. The faces of the prism are characterized by transverse shading. Most often, crystals have an elongated prismatic appearance with the predominant development of the faces of a hexagonal prism and two rhombohedrons forming the crystal head. Less commonly, crystals take the form of a pseudohexagonal dipyramid. Externally regular quartz crystals are usually complexly twinned, most often forming twinned areas according to the so-called. Brazilian or Dauphinean laws. The latter arise not only during crystal growth, but also as a result of internal structural rearrangement during thermal β-α polymorphic transitions accompanied by compression, as well as during mechanical deformations.
In igneous and metamorphic rocks, quartz forms irregular isometric grains intergrown with grains of other minerals; its crystals are often encrusted with voids and almonds in effusive rocks.
In sedimentary rocks - nodules, veinlets, secretions (geodes), brushes of small short-prismatic crystals on the walls of voids in limestones, etc. Also fragments various shapes and sizes, pebbles, sand.

VARIETIES OF QUARTZ

Yellowish or shimmering brownish-red quartzite (due to inclusions of mica and iron mica).
- layered-banded variety of chalcedony.
- violet.
Binghemite is iridescent quartz with goethite inclusions.
Bull's eye - deep crimson, brown
Volosatik - rock crystal with inclusions of fine needle crystals of rutile, tourmaline and/or other minerals that form needle crystals.
- crystals of colorless transparent quartz.
Flint - fine-grained cryptocrystalline silica aggregates of variable composition, consisting mainly of quartz and to a lesser extent chalcedony, cristobalite, sometimes with the presence of a small amount of opal. Usually found in the form of nodules or pebbles that arise when they are destroyed.
Morion is black.
Overflow - consist of alternating layers of microcrystals of quartz and chalcedony, never transparent.
Prazem is green (due to inclusions of actinolite).
Prasiolite is onion-green, obtained artificially by calcining yellow quartz.
Rauchtopaz (smoky quartz) - light gray or light brown.
Rose quartz is pink.
- cryptocrystalline fine-fiber variety. Translucent or translucent, color from white to honey-yellow. Forms spherulites, spherulite crusts, pseudostalactites or continuous massive formations.
- lemon yellow.
Sapphire quartz is a bluish, coarse-grained quartz aggregate.
Cat's eye - white, pinkish, gray quartz with a light tint effect.
Hawkeye is a silicified aggregate of bluish-gray amphibole.
Tiger's eye - similar to hawk's eye, but golden brown in color.
- brown with white and black patterns, red-brown, brown-yellow, honey, white with yellowish or pinkish layers. Onyx is especially characterized by plane-parallel layers of different colors.
Heliotrope is an opaque dark green variety of cryptocrystalline silica, mostly fine-grained quartz, sometimes mixed with chalcedony, oxides and hydroxides of iron and other minor minerals, with bright red spots and stripes.

ORIGIN

Quartz is formed during various geological processes:
Directly crystallizes from acidic magma. Quartz contains both intrusive (granite, diorite) and effusive (rhyolite, dacite) rocks of acidic and intermediate composition, and can be found in igneous rocks of basic composition (quartz gabbro).
In acidic volcanic rocks it often forms porphyry phenocrysts.
Quartz crystallizes from fluid-enriched pegmatite magmas and is one of the main minerals of granitic pegmatites. In pegmatites, quartz forms intergrowths with potassium feldspar (pegmatite proper); the internal parts of pegmatite veins are often composed of pure quartz (quartz core). Quartz is the main mineral of apogranitic metasomatites - greisens.
During the hydrothermal process, quartz and crystal-bearing veins are formed; alpine-type quartz veins are of particular importance.
Under surface conditions, quartz is stable and accumulates in placers of various origins (coastal-marine, aeolian, alluvial, etc.). Depending on the various conditions formation, quartz crystallizes in various polymorphic modifications.

APPLICATION

Quartz is used in optical instruments, in ultrasound generators, in telephone and radio equipment (as a piezoelectric), in electronic devices (“quartz” in technical slang is sometimes called a quartz resonator - a component of devices for stabilizing the frequency of electronic generators). IN large quantities consumed by the glass and ceramics industries (rock crystal and pure quartz sand). Also used in the production of silica refractories and quartz glass. Many varieties are used in jewelry.

Quartz single crystals are used in optical instrument making for the manufacture of filters, prisms for spectrographs, monochromators, and lenses for UV optics. Fused quartz is used to make special chemical glassware. Quartz is also used to produce chemically pure silicon. Transparent, beautifully colored varieties of quartz are semi-precious stones and are widely used in jewelry. Quartz sands and quartzites are used in the ceramic and glass industries

Quartz - SiO 2

CLASSIFICATION

PHYSICAL PROPERTIES