For centuries the chemical element antimony has played an important role in a lot of applications that people gave it before it was discovered that even in small amounts it can cause great problems in the body.
For example, in ancient Egypt and in various parts of Asia, antimony sulfide (Sb2S3) was used as makeup to darken the eyes. Currently it is very important because it has several industrial and technological uses.
Antimony in chemistry and the periodic table
In chemistry the antimony (Sb) is considered as a chemical element which is part of the metalloid group and is characterized by having atomic number 51, therefore it is in group 15 of the periodic table of elements. Therefore this element is basically a semi-metal.
Antimony in geology and mineralogy
In this regard, antimony is considered a metallic or semi-metallic native mineral, therefore it is part of the select group of native minerals.
Very rarely this element appears in nature in abundance, rather it is extracted from other minerals that contain antimony such as stibnite, which is basically a antimony sulfide.
Finally, it should be mentioned that due to its varied applications and importance, it is considered an industrial mineral
Properties and characteristics of antimony
Physical properties
At first glance, this element appears bright and with a silvery-white color typical of metals and semi-metals. In addition, it has a scaly surface, is hard, and breaks easily with a little effort.
However, it can also be found in nature as a shiny black powder.
Its melting point is 630°C and its typical boiling point is 1635°C. It can also be mentioned that it is a soft material that can easily be scratched with a piece of glass or quartz.
Because it is considered a metalloid, it has characteristics of both metals and nonmetals.
| Atomic number | 51 |
| Atomic mass | 121.75 g.mol-1 |
| Electronegativity according to Pauling | 1.9 |
| Density | 6.684 g.cm-3 |
| Melting point | 631°C |
| Boiling point | 1587°C |
| vander waals radius | 0.159nm |
| ionic radius | 0.245nm(-3);0.062nm(+5);0.076nm(+3) |
| isotopes | 12 |
| Electronic configuration | [Kr] 4d105s25p3 |
| First ionization energy | 834 kJ.mol-1 |
| Second ionization energy | 1595 kJ.mol-1 |
| Energy of the third ionization | 2443 kJ.mol-1 |
| standard potential | 0.21V (Sb3+/ Sb) |
Chemical properties
The antimony It is considered a moderately active element, therefore it does not combine chemically with oxygen at ambient or normal conditions. It also does not react readily with ice water or cold acids.
However, it can be recognized because it dissolves in some hot acids and also on contact with aqua regia (a mixture of hydrochloric and nitric acid).
Geological and mineralogical properties
In geology and mineralogy it is known that it is a native element that is not very abundant in nature, in fact the largest amount of antimony is extracted from the mineral stibnite, which is basically a sulfide that contains 72% antimony and 28% sulfur in its composition. chemistry.
When it appears as a native mineral, it is recognized by its very low hardness on the Mohs scale, which is 2, therefore it can be scratched with a fingernail.
Visually it can be recognized because it occurs in small, thick, tabular pseudocubic crystals. In rocks it occurs massive, foliated and granular. It has a lustrous silvery appearance, with bluish-white hues, and it has a scaly appearance that makes it brittle to the touch.
| Class, Group | native element, metalloid |
| ore ore | Stibnite (Sulphide) |
| chemical formula stibnite | sb2s3 |
| Stripe | silvery, off-white |
| Mohs hardness | two |
| crystalline system | orthorhombic |
| Color | Lead gray, blackish or iridescent; in polished section, white |
| Gloss | Metal |
| Fracture | subconchoidal |
| Tenacity | Fragile |
Geological occurrence and genesis
It is quite typical that it appears associated with medium-temperature hydrothermal veins (over 160°C), almost always accompanied by arsenic and which together can give indications of the proximity of anomalies in the presence of silver, gold and antimony metals.
Therefore antimony is found in small amounts together with silver ores, copperY lead, and usually this element is extracted as a by-product in the extraction of those metals.
It is very rarely found in its native state, that is, as an element. Instead, it almost always occurs as a chemical compound in the form of a mineral. Thus, the most common antimony minerals are stibnite, tetrahedrite, bournonite, boulangerite and jamesonite.
In these minerals, antimony chemically combines with sulfur to create sulphide minerals.
Antimony deposits
As mentioned, antimony generally appears in hydrothermal veins, possibly associated with precious metals in hydrothermal and epithermal deposits. Of the geologists study anomalies of this element to find indications of possible gold deposits, through geochemical techniques.
Although epithermal deposits are common in volcanic arcs associated with subduction zones, it does not occur in all countries, in fact currently the largest producers of antimony are China, Russia, Bolivia, South Africa and Kyrgyzstan, in that order. USA produces antimony as a by-product at a single silver mine in Idaho.
What is antimony used for?
Currently the antimony is used for many technological and industrial purposes.One of the main applications is as alloy hardener for lead, especially in storage batteries and cable jackets, and is also used in bearing metal, metal type, solder, collapsible sheet and tube, sheet and pipe, and semiconductor technology.
It has been mentioned that this element mainly comes from stibnite, the same that is used for metal alloys, shot, batteries and in the manufacture of fireworks.
Also the antimony salts they are used in the textile and rubber industry, in medicine and glass manufacturing.
To produce chemicals
The most important application of antimony in the United States it is in the manufacture of various chemicals used to impregnate plastics, textiles, rubber, and other materials used in fire prevention.
These products are called fire retardants and are essential elements in the textile and paper industry in fire prevention.
In technology and semiconductors
A small amount of highly purified metallic antimony is used in the computer industry to make semiconductors. To be useful in this application, antimony must be 99.999% pure.
Is it toxic?
Although it is considered an industrial mineral, it is worth mentioning that is considered to be toxic In fact, in small amounts it can cause serious conditions to the body. It is recommended to follow a strict security protocol for those who work with this element.