Geology Home Page physical geology historical geology planetary gems
Roger Weller, geology instructor
by Luis Angel Flores
Silver is probably one of the earliest metals that were discovered
by the humans, the origin of the word is
the feminine of the adjective
plattus (plate, flat) that in the tenth century, is substantive in the sense of
foil. Its symbol on the periodic table is (Ag), it has the atomic number of
forty seven and the atomic weight is of one hundred and seven thousand
eight hundred seventy. Some ways to identify the chemical silver itís by its
characterics, which are that it has its
system which is cubic. Habit are
very rare in cubic crystals or ortoťdricos, always small in size, usually have
either stepped faces deformed by contact, is usually found in the form of
dendrites, thin sheets. Hardness: 2.5. Density: 10.5. Color: white, gray-blue.
Raya: silvery white. Brightness: very intense metal, although almost always
obscured by a blackish patina due to surface alteration. It is soft, ductile and
malleable. It is a white lustrous metal-gray. From the chemical point of
view, is one of the heavy metals and noble, from the point of view, is a
precious metal. There are 25 isotopes of silver. Their atomic masses ranging are
from 102 to 117.
Some qualities that can be found on silver is that silver It is the best conductor of heat and electricity. It is in the native state (usually alloyed with copper and gold), forming minerals such as argentite, which is silver sulfide. It is much more abundant than gold is mixed with sulfur oxidation zones or other deposits. Pure silver is a moderately soft metal (2.5-3 on the Mohs hardness scale), white, a little harder than gold. When polishing a bright luster acquires and reflects 95% of the light that strikes it. Its density is 10.5 times that of water. Silver quality, purity, expressed as pure silver parts per 1000 parts of total metal. The commercial silver has a purity of 999 (Act 0999). Silver is stable in air and water, but becomes black in the presence of small amounts of sulfur, by formation of silver sulfide and chemically quite inert. Although silver is chemically more active noble metal is not very active compared to most other metals. No rust easily (such as iron). In most of its applications, silver is alloyed with one or more metals. Silver, which has the highest electrical and thermal conductivity of all the metals, is used in electrical contact points and addresses. It is also widely used in jewelry and various parts. Among the alloys in which is a component are dental amalgams and metals for engine bearings and pistons. The process for extracting silver from its mines it is called profit, and consists on various stages such as:
The Extraction which is the area that is prepared to blow, this is called (front or sky) this is accomplished by placing plastic explosive cartridges in holes made by a drill, it is connected to a wick which is called termalita which at their ends is placed a terminal known as capsules, one allowing light the wick and the other which detonates the explosive. After blow, the material that accumulates is loaded by pneumatic blade gondola carts, moving it to piggy-denominated deposits are charge storage containers and then be transferred by the General cloak (collection) to the hoppers (large size funnel and pipeline intended to deposit granular or powdered materials).
Now it will be talked about some interesting facts about the metal
silver, starting off by one of the most important questions which is what itís
silvers origin. Silver is a very scarce item. Sometimes found in nature as a
free element (native silver) or mixed with other metals. However, most often
found in ores containing silver compounds. The main minerals are argentite
silver, or the silver horn cerargirita and various minerals in which the silver
sulfide is combined with other metal sulfides. Approximately three quarters of
the silver produced is a byproduct of the extraction of other minerals,
especially copper and lead. The
native silver is found in hydrothermal veins with sulphides and in the oxidation
zone of the deposits of polymetallic silver and some where it forms due to the
complex sulfur Argentite and silver salts. It is formed by reduction of the
sulfides in the bottom of overburden of the deposits of lead-zinc-silver.
Sometimes it is also found as a primary benefit of the low-temperature
hydrothermal veins as Calcite associated element, or in high temperature
hydrothermal veins like element associated with the sulphides of nickel and
cobalt and uraninite. Silver represents value, this is a reason by which most
coins are made out of silver.
Since silver has the meaning of value and has this mystic feeling through people
it was also implemented to be used on jewelry. The value of silver can go up
suddenly if it is found in a big amount. The graph below shows how on a silver
mine how much the price and earnings of the mine went to the roof in just a
couple of days.
Although silver looks like a wonderful thing it also has a bad side if not used correctly since as many other minerals or metals it can be toxic as well. The effects on health caused by silver are various such as: Liver damage, kidney damage, lung damage, brain damage, anemia and eye damage too. In the eyes it may cause severe damage to the cornea if the liquid comes in contact with eyes. With skin contact may cause skin irritation. Prolonged and repeated contact with skin it may cause allergic dermatitis. The inhalation hazards cause that exposure to high concentrations of vapor may cause dizziness, breathing difficulties, headaches or respiratory irritation. Extremely high concentrations may cause drowsiness, spasms, confusion, unconsciousness, coma or death. The liquid or vapor can irritate the skin, eyes, throat or lungs. Intentional misuse by deliberately concentrating consisting of product and inhaling the contents may be harmful or fatal. Also Heart abnormalities have been reported on the relationship between prolonged and repeated exposure to solvents and brain damage and permanent nervous system. Repeated breathing or skin contact of methyl ethyl ketone may increase the potency of neurotoxins such as hexane if exposures occur simultaneously. Overall silver can be a beautiful and very useful metal but if used without warning it can be a real bad to our health, still silver has a lot more useful and positive things over the bad and negative ones.