Igneous or Metamorphic
Formation of Granite

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Igneous or Metamorphic
Formation of Granite
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Igneous is one of three rock types, Granite is one of many igneous types

Igneous or Metamorphic

Reading time: 15 mins

Granite Geology Brief

Geology is the study of earths natural and mineral rersources, in terms of granite geology, it is debated whether granite is igneous or metamorphic in origin, as the process takes millions of years. The process of granite formation described here can only be speculative even by geologists. According to the origins of the names, the descriptive meanings describe both initial and end process of the formation of granite types - ideally, for simplicity, this would be better described either as 2 types, or combined as Igneomorphic which is uncommonly used.

The following provides a brief granite geology overview of the formation of granite as an intrusive igneous rock. Forming initially as magma to the evolution of one of many resulting rock types 'granite'. Granite is found throughout the world and is processed and mined for many wide and varied uses and requires extraordinary stonemasonry skills both in our hidden history and with today's modern machinery.


The name 'Granite' origins from the Latin word 'Granum' meaning 'Grain'. The structure of granite is coarse-grained crystalline Rock


From Greek, 'Geo' meaning earth and 'Logos' as in philosophy of study through principles, speech and thought.


Igneous is derived from the Latin Word 'Ignis' which means fire. Because igneous Rock is formed from magma


Metamorphic is derived English 'Meta' and greek 'Morphe' to denote a change in condition

Granite Formation


The granite journey begins with 'Magma' which can either cool above ground (Extrusive) or below ground (Intrusive), its exposure to the elements within its environment will alter the properties alchemically and the speed in which it cools. The resulting cooled and hardened mixture (sometimes through compression) is the basis of all igneous rocks and are classified into 4 catergories depending upon the chemistry and mineral composition.


Rich in Silica and Alkali Metal Oxides


Felsic materials mainly Plagioclase and Mafic materials mainly of hornblende, pyroxene, and/or biotite - Quartz content is Low.


Rich in Silica, Magnesium and Iron - Minerals include: olivine, pyroxene, amphibole, and biotite.


Mantle and Primarily of Olivine and Pyroxenes.

Igneous Types

Igneous rock or magmatic, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous types include granite, andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, monzonite, granodiorite, diorite, gabbro and tuff and can be further classified into the following igneous types according to their formation:

Extrusive igneous

Magma exposed and cooled near or above ground solidify to form Extrusive igneous rocks

Intrusive igneous

Magma cooled below ground solidify to form Intrusive igneous rocks after a longer cooling process and allows for a longer crystallization process, resulting in larger crystals.

Plutonic igneous

Magma cooled deep inside the earths crust and solidifies to form Plutonic igneous rocks of which Granite is most abundant, these are referred in some instances as parental rock as they can over time melt or part melt and flow up to the surface, however, the processes this deep are vague and only speculative.

Granite Evolution

Now that the parent material of igneous rocks has been briefly described, The evolution of granite and how the many colours and patterns start to form begins...


As touched upon at the magma stage its exposure to the elements within its environment will alter the properties alchemically and the speed in which it cools. The granite may undergo many pocketed melts also known as 'granatic melts' during its ascent toward the surface. During this metamorphism process the granite will become more highly evolved through fractional crystallization, partial melting and mixing of nearby sedimentary and metamorphic rocks and further enrichment of minerals and extraction of others. A process that is presumed to last millions of years and cycles continuosly through migration back to the depth of the mantle to be remelted back to Magma.



The content of each mineral in granite deposits creates the wide variety of colors through the fractionilisation process

Feldspar (Alkali/Plagioclase) - pink or red
Mica (biotite) - dark brown or black
Mica (Mucovite) - Yellow
Quartz - clear pink, white, or black
Amphibole (Hornblende) - Green, yellow, blue, brown and black
Olivine - Pale Green
Pyroxene - Dark Green

Chemical Composition

Average Granite Chemical composition (some in the form of oxides)

Silicon - 70 t0 77%
Aluminium - 11 to 15%
Potassium - 3 to 5%
Sodium - 3 to 5%
Calcium - 1 to 2%
Iron - 2 to 3%
Less than 1% - Magnesium, Titanium, Phosphorus, Manganese

Physical Properties

Average density of Granite is between
2.65 and 2.75 grams per cm cubed (165 and 172 lb/cu ft)

Granite Compression strength averages above
200 MPa (approx 2 tonnes per square centimetre)

Viscosity near Standard Temperature Pressue
averages 45 grams per cubic centimetre

Dry Granite Melting temperature at ambient pressure
1215–1260°C (2219–2300 °F)

Wet Granite Melting Temperature
650°C (a few kBar of pressure)

Granite Processing

Granite Outcrops

Found worldwide in what is called 'Granite Outcrops' such as 'tors' (mountains), 'domes', 'bornhardts', and 'rounded massifs'. Outcrops can sometimes appear as circular depressions surrounded by a range of hills, formed by the metamorphic aureole or hornfels. Most granite outcrops are less than 100 km2 stock masses and in batholiths that are often associated with orogenic mountain ranges, also small dikes of granitic composition often associated with the margins of granitic intrusions are called aplites.

Exporters of Granite

Major modern exporters of granite include

Canada, China
India, Italy
Spain, Sweden,
and the United States

Granite Uses

Granite is mined generally as crushed or as dimension stone for construction, some examples of mined form uses:

Crushed granite: Asphalt, Concrete, Roads, Railroads & Infrastructure
Blocks: Land stabilizing, Construction, Memorials, Monuments & Decor
Slabs: Veeners, Cladding, Flooring, Granite Worktops & general decor

Granite in Stonemasonry


One of the oldest human activities and professions, 'Stonemasonry' is the building of structures and sculptures. Most ancient buildings of the near and far distant past were built from stone and many still stand today, albeit weathered, thousands of years later. Not only were these buildings built with incredible precision but with an intricacy that we do not replicate today.

Stonemasonry roles are branched and specializations can be divided innto the following job roles: Quarrymen, Sawyers, Banker masons, Carvers, Fixer Masons, Memorial Masons. Mgm & rocks Ltd still finish by hand as that feel of a hand finished polish provide what machines cannot achieve

Hidden History of Granite

Until the early 18th century it is taught that granite could be carved only by hand tools, and even then, the new world machinery could not rival the mastery of stoneworking of times past. Modern research into architecture of the near and far distant history provides evidence of machining and most likely a technology that involved water, sound and vibrations. This is evident in the far distant past of megalithic structures and more recent 'middle (hidden) age' star forts/cities located worldwide. Unfortunately, the new revelations of the past have not yet made its way into the history books nor has it been acknowledged for teaching and training purposes for fear of modern humans questioning the current narrative.


A word used by a British antiquarian Algernon Herbert in 1849 in reference to Stonehenge, 'Megalith' in greek means Big Stones'. With over 35,000 megalithic structures in europe alone, it is shameful that academic research has not recognised the complexity and sheer manpower that was required to erect such monumental structures worldwide, maybe it because that we are unable to duplicate the feats achieved an how the construction style is consistent the whole world over at a time when worldwide communication was supposed not to exist. The accuracy in which the 'big stones' were adjoined without any cementing is unfathomable when a piece of paper cannot penetrate the joins.

The biggest of all are those structures are carved out of the solid rock face or rock bed itself, such as 'Lalibela' in Ethiopa and 'Petra' in Jordan. In our modern times of lesser quality and passion into construction we are ignorant to believe that any ancient construction is found to automatically presume that these were either tombs or places of worship and that hand tools could carve what our modern machinery cannot.

Modern Machinery

Advances in electric motor driven technology over the past few centuries allows for brute force and speed to cut through stone with the addition of water, the inclusion of diamonds as an abrasive added to blades and CNC tools allows for an easier and cleaner cut. Although the force with modern machinery is against natures simplified methods of sound and vibration, new technologies are slowly and reluctantly realigning themselves with nature. Water Jet is one of the most recent advances in cutting technology.


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