Gold is one of the native metals and minerals most appreciated by human beings due to its beauty and its physical and chemical properties that make it very useful, it is true that native gold is widely used in jewelry, however, it is a metal with great characteristics that are applied in various industries, especially in current technology.
For geologists it is known that the native gold is mainly associated with low and high sulphidation vein, orogenic and epithermal deposits.
Tentatively, it can be said that it is the most useful metal of all, it is applied in jewelry, technology, prizes, coins, dentistry, medicine, cars, ships and many other things.
We have a complete article on all the uses of gold, check it out by clicking here.
The importance of native gold
the history of native gold It dates back to Egyptian times, where it was mostly used for kings. From then until now, the use of gold has undergone multiple alterations that have led to having it in different presentations.
When Spanish explorers first arrived in the “New World” they encountered natives of South America. They were different cultures, yet they had one thing in common: they both held gold in high esteem.
Since ancient times, gold has symbolized power or achievement. It is the most positioned metal in society for its value.
Properties and characteristics of native gold
native gold | Properties and characteristics |
---|---|
chemical classification | native element |
Color | Golden yellow. Bleaches when naturally alloyed with silver. |
Stripe | Golden yellow. |
Gloss | Metallic, untarnished. |
diaphanousness | Opaque |
cleavage | None |
Mohs hardness | 2.5 to 3 |
Density and specific weight | 19.3 when pure. Specific gravity decreases as gold naturally alloys with silver, copper, or other metals. |
diagnostic properties | Color, hardness, streak, specific gravity, ductility, malleability. |
Chemical composition | Gold, Au |
crystalline system | isometric |
Associated minerals | Quartz, pyrite, chalcopyrite, galena, sphalerite, bornite, realgar, marcasite, cinnabar, magnetite. |
Applications | Many uses in jewelry, coins, and bullion. Gold is an electrical conductor used in computers, circuits, appliances, cell phones, etc. Dental work, gold leaf and many other uses. |
There are some physical properties that stand out from the native gold ore, for example, is a very malleable metal, so much so that an ounce of gold could be stretched like a thread for about 50 kilometers.
In addition, it is very resistant to corrosion and oxidation in the environment, which makes it attractive for use in high-quality jewelry and chips, electronic microprocessors that are applied to computers and cell phones.
In addition, it is one of the best electrical conductors that exists, which is why it is widely used as an electronic component, in cell phones, in car construction, and in household appliances.
It is a native element, so its chemical formula is Au (gold), its Mohs hardness is quite low at 2.5 to 3 (it is easy to scratch it with quartz) and its density is 19.3 which is considered high.
Often times you can confuse native gold ore with other very similar minerals, but its physical properties will help to distinguish it, for example, the line that is golden in gold.
How to identify native gold?
As mentioned at the beginning, the native gold It is usually confused with other minerals, the most common example is to confuse it with pyrite, in the so-called fool’s gold.
However, this precious metal has several distinctive characteristics and properties, for example:
The native gold ore it has a characteristic golden metallic sheen. It is easy to scratch it with a nail made of iron, steel and quartz, because its Mohs hardness is 2.5 to 3, and the color of the scratch is golden.
It is a very malleable metal, which means that it can be easily transformed into sheets, gold threads, and an infinity of shapes.
It is quite heavy and dense.
Next, we present some tables that show you the differences that gold has with other similar minerals, we also recommend you read the article on fool’s gold and minerals that are similar to gold by clicking here.
Difference Between Gold and Pyrite
Properties and characteristics | Prayed | Pyrite |
---|---|---|
Color | bright golden yellow | Pale yellow |
Mohs hardness | 2.5 to 3 | 6, 6.5 to 7 |
stripe color | golden yellow | Dark green |
way of introducing yourself | massive, granular | mainly cubic |
Changes | does not rust | rusts easily |
Chemical composition | Ow, native | Iron Sulfide (FeS2) |
Malleability | Very malleable, it does not break and deform (it can be easily shaped in various ways) | It is very fragile, it breaks easily |
Difference Between Gold and Chalcopyrite
Properties and characteristics | Prayed | chalcopyrite |
---|---|---|
Color | bright golden yellow | Yellow with a slight greenish hue |
Mohs hardness | 2.5 to 3 | 3.5 to 4 |
stripe color | golden yellow | Dark green |
way of introducing yourself | massive, granular | Massive, granular, but often looks like flakes or sheets |
Changes | does not rust | It rusts and spoils easily. |
Chemical composition | Ow, native | Copper iron sulfide (CuFeS2) |
Malleability | Very malleable, it does not break and deform (it can be easily shaped in various ways) | It is very fragile, it breaks easily |
How was native gold formed?
The native gold Like the other elements in nature and the universe, it comes from the enigmatic big bang, that is, it was formed in the explosion that gave rise to the universe.
When that explosion occurred, all the elements on the periodic table and their possible combinations were being formed to get an idea from the lightest to the heaviest.
This means that gold was formed long after helium.
When gold was already formed, this same metal was transported by the expansion of the universe itself through meteorites, and several successive explosions that occur in space.
This is how it came to our planet, through the successive accumulation of pieces of incandescent rocks that were part of the process of formation of the earth.
Here the gold accumulated in the mantle of the planet and is transported towards the crust by hydrothermal fluids.
Why do we find native gold on the surface?
Because the native gold ore it is a very dense and heavy metal, we might think that it exists in large accumulations in the core, mantle and deeper parts of the crust.
The truth is that gold is a highly mobile element and tends to be transported by hydrothermal fluids to upper parts of the crust in punctual accumulations, known as gold deposits or deposits.
How does it happen?
Hydrothermal fluids that come from magmatic bodies in the crust contain many metals, including native gold However, this metal is not found as a free element in the hydrothermal magmatic fluid, but rather, it is found forming chemical complexes, especially gold sulfides.
These chemical complexes are stable at a certain pressure and temperature, if the system changes conditions, that is, the pressure and temperature decrease, the native gold It is deposited in the empty spaces of the rocks with other associated minerals such as quartz, pyrite, chalcopyrite, sphalerite, galena, etc.
The most typical structure where gold deposits are found are veins, veinlets or veins that cut the rocks.
What is a gold vein?
A gold vein is a body that has a regular elongated tabular shape, which cuts through the rocks and is usually enriched in minerals and minerals of economic interest, such as chalcopyrite, sphalerite, galena, etc.
This vein is formed by the rise of hydrothermal fluids from the depths of the crust to the surface, which cut the rocks and deposit minerals and metals of economic interest such as gold.
These veins are recognized because they are usually rich in minerals, they are of a regular width that varies between 1 centimeter to a few meters, while their length can reach several kilometers.
Finally, it can be mentioned that these veins are structurally controlled, that is, they are associated with geological fault systems, so they are usually parallel and perpendicular to each other according to the fault system.
What are gold nuggets?
Gold nuggets are basically pieces of gold that have been washed down from the gold veins that are generally found in the mountain ranges to lower parts.
These gold nuggets are usually transported by river water, for this reason there are many artisanal miners who look for gold on the river terraces, since they accumulate in sectors where the river is calmer and allows the sedimentation of minerals and metals of interest.
These nuggets are characterized by the fact that they can even be of a size that sometimes exceeds 1 centimeter in diameter, and if large accumulations are found, they can be exploited as a fluvial gold deposit known as placer-type deposits.
Some interesting facts about gold
- The atomic number of native gold, which means that there are 79 protons in the nucleus of each gold atom.
- One ounce of the precious metal can be stretched to a length of 50 miles; the resulting wire would be just five microns wide.
- an ounce of pure gold it can be hammered on a single sheet of nine square meters.
- Julius Caesar gave two hundred coins of the precious metal to each of his soldiers from the spoils of war upon defeating Gaul.
- Fort Knox has 4,600 tons of gold.
- The United States Federal Reserve has 6,200 tons of gold.
- The temperature of the human body is 37 degrees.