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Origin Of  Name: From the Greek word ‘oblique’ in reference to anorthite’s crystal shape. Copyright: geology.today Physical properties:-   Hardness: 6 to 6.5 Cleavage: perfect(001), good(010), poor(110) Specific gravity: 2.76 Fracture: Uneven Luster:  vitreous to pearly Transparency: translucent Colour: white, gray,  Streak: white Crystal system: triclinic Occurance:  Anorthite is a rare compositional variety of plagioclase. It occurs in mafic igneous rock. It also occurs in metamorphic rock of granulite facies, in metamorphosed carbonate rocks,  and corundum deposits.    Uses:    it is used in the manufacture of glass and ceramics.

Origin Of  Name:  From the Latin word ‘Albus’,meaning white. Copyright: geologypage.com Physical properties:- Hardness: 6  Cleavage: perfect(001), good(010), poor(110) Specific gravity: 2.62 Fracture: Uneven Luster:  vitreous to pearly Transparency: transparent to translucent Colour: white, gray, green Streak: white Crystal system: triclinic Occurance:  *Albite is common in granites, granodiorites, rhyolite and syenite.  *In metamorphic rocks it is common in pelitic rocks, a fine-grained sedimentary rock that has been metamorphosed. An example of a pelite is mudstone.     Uses:   *Albite is used as a gemstone. *Some industrial use are in the manufacturing of glass and Ceramics.

Introduction:  Silicates are a fascinating and diverse group of minerals that form the foundation of the Earth's crust. They are composed of silicon and oxygen, the two most abundant elements in the Earth's crust. Silicates exhibit a wide range of chemical compositions and crystal structures, making them crucial components of rocks, soils, and various industrial applications. The fundamental unit in the building of silicate minerals is the  SiO 4 -4  tetrahedron in which the silicon atom is situated at the centre of tetrahedron where corners are occupied by four oxygen atoms. The radius ratio of Si +4  to O -2  requires that Si +4   be coordinated by 4 O -2  ions in tetrahedral coordination. In order to neutralize the +4 charge on the Si cation, one negative charge from each of the Oxygen will reach the Si cation. Thus each Oxygen will be left with a net charge of -1, resulting in a SiO 4 -4  tetrahedral group that can be bond to other cations. It is this SiO 4 - tetrahedron th

Ice age, also called glacial age, any geologic period during which thick ice sheets cover vast areas of land. Such periods of large-scale glaciation may last several million years and drastically reshape surface features of entire continents. A number of ice ages have occurred throughout Earth history. The earliest known took place during Precambrian time dating back more than 570 million years. The most recent periods of widespread glaciation occurred during the Pleistocene Epoch (2.6 million to 11,700 years ago). A polar map shows five great ice caps or centres from which the ice moved outward during the ice age and to which it later retreated Copyright: Encyclopaedia Britannica, Inc. A lesser, recent glacial stage called the Little Ice Age began in the 16th century and advanced and receded intermittently over three centuries in Europe and many other regions. Its maximum development was reached about 1750, at which time glaciers were more widespread on Earth than at any t

The snow-capped mountains Himalayan range is the tallest and the youngest in the world. It is also known as the "Abode of God" and people worships the mountain range as a form of divinity. Not only are the mountains a perennial source of water, but also support plant, animal and human life. Adventure seekers and the nature lovers find home in the mountains. 1. Mount Everest, Himalayas, Nepal/Tibet Autonomous Region, China- 8,848 m (29,029 feet) Mount Everest, Sanskrit and Nepali Sagarmatha, Tibetan Chomolungma , Chinese (Pinyin) Zhumulangma Feng  or (Wade-Giles romanisation) Chu-mu-lang-ma-Feng , also speller Qomolangma Feng , mountain on the crest of the Great Himalayas of southern Asia that lies on the border between Nepal and Tibet Autonomous Region of China, at 27°59'N 86°56'E. Reaching an elevation of 29,029 feet (8,848 metres), Mount Everest is the highest mountain in the world. Copyright: Arsgera/iStock.com Like other high peaks in the

Origin Of Name: From the Greek word ‘micros’ means ‘small’ and ‘Klinein’ means ‘to lean’, referring to this mineral’s cleavage angles being 90⁰. Copyright: Britannica.com Physical properties: . Hardness: 6 . Cleavage: perfect on(001) , good on(010) . Specific gravity: 2.56 . Fracture: Irregular/uneven . Luster:  Vitreous . Transparency: Transparent to translucent . Colour: white to pale yellow, more rarely red    or green . Streak: white Crystal system: Triclinic Occurence: . Microcline is a prominent constituent of igneous rocks such as: granite and syenite that cooled slowly at and at considerable depth. . In sedimentary rocks it is present in: Arkose and Conglomerate. . In metamorphic rock present in: gneiss. . It is a common K-feldspar of Pegmatites.  Uses: Feldspar is used chiefly in the manufacture of Porcelain. . A small amount of feldspar is used in the manufacture of glass to contribute alumina to the batch. . It is used as ornamental lapidary material with a

Origin Of Name From the Greek word sants  (tablet) and idioms (appearance), referring to this mineral's typical habit     Copyright: geologyscience.com Physical Properties: . Hardness- 6 . Specific Gravity- 2.56 . Clevage- Perfect (001) . Fracture- Good (010) . Luster- Vitreous . Transparency- Transparent to translucent . Colour- White, variable . Streak- White Crystal System- Monoclinc

The term volcano means the vent from which magma and other substances erupt to the surface Or when molten rock erupts from an opening on Earth's surface, volcanoes develop. Note: 75% of the world's active volcanoes are underwater. . The ash cloud from a large volcanic eruption can be up to 60 kilometres (40 miles) high.    Mount St. Helens Volcano    ( Copyright: Getty Images) Volcanoes are classified as active, dormant or extinct, based on how they erupt. An "active" volcano is one that is known to have erupted in recent history. A volcano that has not erupted recently but might erupt again is called "dormant". A volcano that has stopped erupting altogether is called "extinct". Since volcanic eruptions are caused by magma ( a mixture of liquid rock, crystals and dissolved gas) expelled onto the Earth's surface. Three Basic types of magma: 1. Mafic or Basaltic- SiO₂ 45-55 wt%, high in Fe, Mg, Ca, low in K, Na 2. Intermediate Or Andesitic-  Si

Origin Of Name From Greek word orthos (right angle) and klasis (to break)     Orthoclase-Serra-de-Peneda-Portugal     Copyright: Emil Javorsky/Encyclopedia              Britannica, Inc. Orthoclase is common in many kinds of silicic igneous rocks, sediments such as arkoses, and a variety of metamorphic rocks. Quartz and micas are typically associated minerals Physical Properties . Hardness- 6 . Specific Gravity- 2.56 . Clevage- 90° clevage angle, perfect (001), good (010), poor {110} . Fracture- Uneven . Luster- Pearly, Vitreous . Transparency- Translucent . Colour- White, pink, turbid . Streak- White Crystal System- Monoclinc Uses- Ceramics, glass, abrasives, gemstones

1. Cinnabar- Cinnabar is the main ore of mercury, the most toxic mineral on Earth. The name itself means dragons bloods. Form near volcanoes and sulphur deposits, the bright red colour signals danger.                    Copyright: Courtesy of Ted Boente; John H. Gerard/Encyclopedia Brittanica, Inc.  2. Orpiment- Originate from Latin auri , " golden "; pigmentum , " paint ". Composed of Arsenic Sulfide, the lethal and chemically reactive orpiment crystals are found growing below the surface in mineral formations, often near hydrothermal veins. It may crumble into dangerous powder when exposed to light. Holding crystals in your hands may release carcinogenic , neurotoxic powder.   Copyright:   U.S. Geological Survey 3. Stibnite- Antimony Sulphide, the principle ore of antimony. It is used in manufacturing of  matches and fireworks. Mines near Oksaku, Japan produce the best stibnite crystals in the world.                                                               

The Kola Superdeep Borehole , deepest manmade hole on Earth and deepest artificial point on Earth is located in the Pechengsky district on the Kola Peninsula in Northwestern Russia. Kola Superdeep Borehole also known as the "entrance to hell" or "well to hell" . Since 1988 Kola Superdeep Borehole is deepest borehole in terms of Vertical Depth and measures 12,262 metres ( 40,230 Ft deep ), ( 12.2 Km ) and 23 cm in diameter.     The Borehole is located in the wild's of  northern Kola Penisula (Credit: Getty Images) Drilling commenced in May 1970 after 10 years of planning by Russian then USSR's Interdepartmental Scientific Council of the Earth's Interior .     The borehole still exists: but the entrance has been welded shut (Credit: Rakot13/CC BY-SA 3.0)  Reference: https://www.bbc.com/future/article/20190503-the-deepest-hole-we-have-ever-dug#:~:text=This%20is%20the%20Kola%20Superdeep,of%20souls%20tortured%20in%20hell.

Origin Of Name From Greek "threefold", triangular wedge-shaped crystals     Copyright: Galleries.com Tridymite is a low pressure, high-temperature-stable Polymorph of Silica that can form metastably at low temperatures Physical Properties . Hardness- 6 to 7 . Specific Gravity- 2.28 . Clevage- None . Fracture- Conchoidal . Luster- Vitreous . Transparency- Transparent to translucent . Colour- Colourless . Streak- White Crystal Structure- Orthorhombic