What is it?
Granite is the most common rock in the continental crust and also my second favorite rock (mostly because I like how it looks). It is an igneous rock. Granite is plutonic intrusive meaning it has solidified deep within the earth's crust
Composition
Granite is felsic so it is over 65% silica which implies it formed in a silica-rich part of the earth's crust.
Granite's predominant mineral is alkali feldspar which gives granite a pinkish color, however, this mineral may also be colored white, buff, or grey. granite may also contain plagioclase feldspar and this ratio has given us a way of classifying the rock, if plagioclase feldspar greatly exceeds the alkali feldspar the rock is granodiorite. Granite is also 10% quartz which can be grey. granite's other major minerals are mica ( black) and sodium. Granite also has a medium to the coarse-grained texture ( this means that individual crystals are visible).
Formation of granite
Granite crystallizes from silica-rich magmas at extreme depths. Due to this depth when granite is exposed to a surface we can assume that uplift has taken place and that the overlying rock has been eroded. When granite crystallizes, many important minerals are formed around the rock, from hydrothermal solutions released by the granite bodies crystalizing. These minerals include pegmatite gemstones such as topaz; rock crystal; tourmaline; aquamarine, and many melliferous ores such as gold; silver; lead, and titanium.
Uses of granite
Formerly granite was quarried, for structures, on a vast scale, due to its strength and durability allowing the building to last many years without too much maintenance. An example of this is the mount, Rushmore. today granite's use for buildings is as a veneer for
aesthetic purposes creating an expensive impression. It is now sometimes used for kitchen worktops and kerbstones.
Problems with quarrying granite
However, this quarrying for granite can be detrimental environmentally as large natural areas are cleared for quarrying this may endanger many animal and plant species and could damage. the planet's biodiversity.
Granite quarrying also causes human health issues. A study (link to paper at the bottom of the page) monitored the level of particulate matter in the air around 5 quarry sites and analyzed the health issues of residents living around these areas. a suspended particulate matter (SPM) meter was employed for measuring the levels of SPM in the air. The data for the quarry workers' health profiles were obtained using hospital records. For the prevalent health problems of residents, a questionnaire was used in two neighboring towns of each site. The results show that SPM levels among the selected quarries vary between 26.03±1.36mg/m3 and 11.03±1.52mg/m3. however, as the distance from the site increased SPM levels declined. At 25 meters away from the sites, mean SPM levels reduced greatly to 4.85±0.20mg/m3 and 3.67±0.40mg/m3. Residents were shown to have health issues: shock (46%); nasal infection (29.2%) and asthma (4.6%). The workers were shown to suffer: predominantly from cough (26.%); catarrh (20.%) and sinusitis (15.%).
This study shows the horrific health problems from quarrying which are not in any way acceptable.
https://www.ajol.info/index.php/ejesm/article/view/43497
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