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Roger Weller, geology instructor
by Rafael Aponte
Calcite, The Mineral With The Most
Calcite is in fact, a carbonate mineral and the most stable
polymorph of calcium carbonate as well as being in a hardness of 3 is nothing
when rubbed with something harder like a corundum or even a piece of apatite. In
a few places in the world, calcite can sometimes get mixed with peoples drinking
water causing ill-effects in the body. A problem that affects people in desert
areas like Arizona or California, and is an issue when it comes to housing and
health. There are ways to know what is Calcite as a mineral, what are the
effects when calcite is dissolved/mix in water to other materials, and how
calcite is formed in the sinks and what causes it.
Showing these might give people an idea of the subject matter at hand to give a
few people to make good choices with drinking water in the desert communities.
The very first question that people have about calcite is “what is
it”, well surprisingly this will be a rundown of Calcite as a mineral and its
uses. Calcite is a rock-forming mineral with a chemical formula of CaCO3
(Calcium + Carbon +Trioxide), it is also an extremely common mineral found
throughout the world in sedimentary, metamorphic, and igneous rocks. Some
geologists consider it to be a "ubiquitous mineral" - one that is found
everywhere (King), Calcite is a component inside such material as limestone and
marble, extremely common rocks that can be found anywhere in the world (even in
a desert). Calcite is also used in a wide range of architectural and
agricultural jobs its used for (King), for example, calcite can be used in a
form of foundation for many buildings that want to appear very pleasing to the
eye. The construction industry is the primary consumer of calcite in the form of
limestone and marble. These rocks have been used as dimension stones and in
mortar for thousands of years. Limestone blocks were the primary construction
material used in many of the pyramids of Egypt and Latin America. Today,
limestone and marble are still an important material that is used in prestige
architecture such as government buildings and if optional, hotels and casinos
Calcite also has numerous uses as to neutralize any acids. For hundreds of years, limestones and marbles have been crushed and spread on fields as an acid-neutralizing soil treatment, they are also heated to produce lime that has a much faster reaction rate in the soil (King). Calcite is used as an acid neutralizer in areas were streams are plagued with acid mine drainage, crushed limestone is dispensed into the streams to neutralize their waters. High-grade optical calcite was used in World War II for gun sights, specifically in bomb sights and anti-aircraft weaponry (Lister). There are many uses when it comes to this commonly found mineral in many places in the world.
Calcite is not the strongest mineral in the world if others know by
now that calcite is in the 3rd mark of the Mohs scale of hardness
when exposed to factors of natural and unnatural occurrences that might be a
factor in the chemical change of calcite. Water by far is the first the first
thing a person might think of when dissolving something
like salt or limestone (but it takes a long time to do so), one example of a
calcite with another chemical is
one study of mixing Zn2 with calcite and two other substances, in
addition to mixtures of calcite with the two other materials,
investigated at various loadings and mixture compositions using atomic
absorption spectroscopy, scanning electron microscopy/energy dispersive X-ray
spectroscopy, X-ray powder diffraction, and Fourier transform infrared
techniques (Shahwan). Coming back to the subject of water, Calcite can be either
dissolved by groundwater or precipitated by groundwater, depending on several
factors like if the temperature of the water is high enough ,
the ph of a certain thing in concentration, and even dissolved ion
concentrations. Although calcite is insoluble in cold water, acidity can cause
dissolution of calcite and release of carbon dioxide gas.
Calcite may be in a way not as strong to withstand acids, but still has its uses
for many things, even when it can't up against lemon juice (or something like
When a person looks at a sink, what do they see, that white residue that resides
around from faucet to the sink, that’s the hardware
aka lime (not the fruit the mineral that’s made mostly out of minerals) that was
built up when water is used, and this is the reason this minor event starts. The
starting point for knowing this stuff is its name, limewater (also known as hard
water when dried) is a clear and colorless liquid substance, with a slight
earthy smell and an alkaline bitter taste of calcium hydroxide (Seidell and
Nostrand). This mixture is formed when groundwater dissolves carbon
dioxides aka CO2 and other material then mixes to become limewater,
calcite, surprisingly actually helps with water being manageable by alkalizing
the water which offsets the acidity (low pH) of water caused by dissolved carbon
dioxide (Calcite Neutralization). Carbon dioxide in small amounts is present in
all-natural waters. In reverse osmosis membranes remove the alkalinity present
in water but not the carbon dioxide, because it is a gas. This creates a low pH
in the product water meaning that the calcite controls the effects of CO2
(Calcite Neutralization). Once again, calcite has more
uses than its credited for
and makes the water people use safely to consume and bath in.
In conclusion, calcite is a common mineral that has many properties and applications that are of great use for many people as well as being common among other minerals that exist on this planet. Calcite is a great mineral when it comes to making buildings and makes medicine for some forms of illness that they help to ease it. Calcite can be dissolved in many forms of reactions and/or acids when it's under the right conditions. The mineral is useful when it comes to regulating other things in the water to balance thing out. Calcite is a material that is very abundant of and has used in many ways for those who know what the properties are and how they apply to peoples lives.
A. Seidell, W. F., Nostrand, Linke, Van. ´Solubility of Inorganic and Metalorganic Compounds - A Compilation of Solubility Data from the Periodical Literature´,(Publisher), 1953
“Calcite Neutralization Filters Information.” Calcite/Neutralization, www.watertreatmentguide.com/calcite_neutralization.htm.
King, Hobart. “Calcite.” Geology.com, Geology.com, geology.com/minerals/calcite.shtml.
Lister, Priscilla. “Borrego's calcite mine trail holds desert wonders.” Sandiegouniontribune.com, 5 Dec. 2010, www.sandiegouniontribune.com/sdut-borregos-calcite-mine-trail-holds-desert-wonders-2010dec05-htmlstory.html.
Shahwan, T., et al. "AAS, XRPD, SEM/EDS, and FTIR Characterization of Zn2+ Retention by Calcite, Calcite-Kaolinite, and Calcite-Clinoptilolite Minerals." Journal of colloid and interface science 286.2 (2005): 471-8. ProQuest. Web. 19 Nov. 2017.