Loria Assignment 1 PDF

Mineral Groups (6 Examples Each) 1. Silicates A. Examples of Silicate: The most prevalent kind of mineral in the Earth's crust is a class of minerals composed of silicate groups. ​ Quartz: A mineral composed of silicon dioxide that is hard and crystalline ​ Feldspar: A mineral composed o...

Mineral Groups (6 Examples Each) 1. Silicates A. Examples of Silicate: The most prevalent kind of mineral in the Earth's crust is a class of minerals composed of silicate groups. ​ Quartz: A mineral composed of silicon dioxide that is hard and crystalline ​ Feldspar: A mineral composed of silicon and aluminum that also includes sodium, potassium, and calcium ​ Mica: a class of minerals with a layered structure and a silicate basis. ​ Olivine: is a silicate mineral of magnesium and iron that makes up a significant portion of the Earth's upper mantle. Additionally, meteorites, the Moon, and some metamorphic rocks contain it.  ​ Pyroxene: the most important and prevalent class of ferromagnesian silicates that form rocks ​ Amphibole: a significant class of hydrous minerals found in many different kinds of rocks. Physical Amphib Properties Quartz Feldspar Mica Olivine Pyroxene ole Colorless, white, Olive silver; green, Dark Biotite: yellow-gre Dark green, Transparent to Black, en, green, black, white, varies with White, pink, brown, brownish- black, brown, Color impurities gray dark green green brown white Pearly to vitreous Vitreous Vitreous to (shiny, Vitreous (glassy) to Vitreous Luster Vitreous (glassy) pearly glassy) (glassy) dull to silky  2.5–3 on the Mohs scale (soft, 6.5–7 on 5–6 on can be the Mohs 5–7 on the the Mohs scratched scale Mohs scale scale by a (relatively (moderatel (moderat Hardness 7 (Mohs scale) 6 - 6.5 fingernail) hard) y hard) ely hard) one direction Poor Two (splits into cleavage planes at Cleavage/F No cleavage, Two planes at thin in two Two set of ~56° and racture conchoidal fracture nearly 90° sheets) directions cleavage 124° Construc tion materials (hornble nde is used in Ceramics, Constructi concrete Glassmaking, glass, on Geological and road Use electronics, jewelry construction materials Jewelry studies building) Table 1: Physical properties of Quartz, Feldspar, Mica, Olivine, Pyroxene, Amphibole. 2. Oxides B. Examples of Oxides: Oxides consist of oxygen bonded to one or more metals. ​ Hematite: a red-brown iron oxide mineral that's a primary ore of iron. ​ Magnetite: A mineral composed of iron oxide that is black and magnetic ​ Corundum: An aluminum oxide that frequently takes the form of thin tabular hexagonal plates or hexagonal barrel-shaped prisms that taper at both ends  ​ Ilmenite: one of the primary sources of titanium dioxide, a black or steel-gray mineral​ ​ Spinel: A mineral that may hold different metal cations in tetrahedral or octahedral locations and is a member of the cubic space group ​ Chromite: The primary source of the metal chromium is a mineral that comprises iron oxides and chromium.  Physical Properties Hematite Magnetite Corundum Ilmenite Spinel Chromite Metallic gray, Black, Black, Black to black, red (ruby) brown, dark Glassy red brownish- dark gray Color reddish-brown gray black Vitreous to Metallic Metallic to Metallic to adamantine Metallic to Vitreous to earthy submetallic (brilliant submetallic (glassy) submetalli Luster shine) c 5.5–6.5 5.5–6.5 on 5.5–6.5 on the on the the Mohs Mohs scale 9 on the 5–6 on the 8 on the Mohs scale (moderately Mohs scale Mohs scale Mohs scale scale (moderately hard) (moderate hard) Hardness ly hard) Cleavage/ None None None None None Fracture None Pigments, Stainless Magnetic Heavy Production of Gemstones steel materials and concrete and Gemstones titanium and productio Iron ore Pigments metal Use Ceramics n Table 2: Physical properties of Hematite, Magnetite, Corundum, Ilmenite, Spinel, and Chromite 3. Carbonates C. Examples of Carbonates: Carbonates have a defining carbonate group (CO₃) ​ Calcite: The most prevalent mineral on Earth is a carbonate. ​ Aragonite: Calcium carbonate polymorphism under high pressure ​ Dolomite: a calcium and magnesium-based sedimentary rock and carbonate mineral ​ Malachite: A vivid green mineral called copper carbonate hydroxide ​ Azurite: The weathering of copper ore deposits produces a soft, deep-blue copper mineral. ​ Siderite: An iron (II) carbonate (FeCO3)-based mineral  Physical Calcites Aragonite Dolomite Malachite Azurite Siderite Properties Bright green, often with Brown, Color white Orange White banded Deep blue yellow-bro patterns of wn, light and dark green Pearly to Vitreous Vitreous Vitreous (glassy vitreous and Vitreous Luster vitreous (glassy) to (glassy) to or crytalize) pearly (glassy) (glassy) silky pearly 3.5–4 on 3.5–4 on 3.5–4 on 3 on the Mohs 3.5–4 on the 3.5–4 on the Hardness the Mohs the Mohs the Mohs scale Mohs scale Mohs scale scale scale scale (soft) cleavage in Cleavage Cleavage Calcite cleaves in cleavage in Cleavage three None in one in one three directions one direction directions direction direction Marine Decorativ Use Building materials Agriculture Pigments Pigments ecosystems e objects Uneven to splintery Conchoida Conchoida Fracture Conchoidal (breaks into Conchoidal Conchoidal l l sharp, fibrous fragments) Table 3: Physical properties of Calcites, Aragonite, Dolomite, Malachite, Azurite and Siderite 4. Sulfides D. Examples of Sulfides: Sulfides include sulfur bonded to metals. ​ Pyrite: An iron disulfide mineral that occurs spontaneously ​ Galena: The main source of lead and silver is a lead mineral. ​ Chalcopyrite: The main source of copper, a copper-iron sulfide mineral. ​ Sphalerite: A zinc sulfide (ZnS) mineral that is honey-yellow and bronze-black. ​ Cinnabar: The primary mercury ore mineral is mercury sulfide (HgS).  ​ Stibnite: An antimony-producing mineral that is soft and lead-gray Physical Pyrite Properties Galena Chalcopyrite Sphalerite Cinnabar Stibnite Lead Yellow, Lead gray to Bright red gray to Color Brass-yellow brassy yellow brown, silvery gray to dark red silver-gra black y Adamantin Vitreous Luster Metallic Metallic Metallic e, resinous, (glassy) to Metallic greasy resinous 3.5–4 on 2–2.5 on 2–2.5 on 6–6.5 on the 2.5–2.75 on 3.5–4 on the Hardness the Mohs the Mohs the Mohs Mohs scale the Mohs scale Mohs scale scale scale (soft) scale Perfect Perfect perfect perfect cubic cleavage in cleavage Cleavage None poor cleavage dodecahedr cleavage one in one al cleavage direction direction Primary Battery Gold Primary ore of Major ore of Primary ore Use source of technolo prospecting lead copper of zinc mercury gy irregular to typically uneven with uneven Conchoidal Fracture Conchoidal Conchoidal metallic luster Conchoidal or to uneven and greenish subconch black streak oidal Table 4: Physical properties of Pyrite, Galena, Chalcopyrite, Sphalerite, Cinnabar, and Stibnite 5. Sulfates E. Example of Stibnite: Sulfates feature sulfur and oxygen with a (SO₄) group. ​ Gypsum: a soft, white, sulfate mineral that's made of calcium sulfate dihydrate ​ Barite: The main source of barium is a mineral (Ba) ​ Anhydrite: It is found in dolomites, limestones, and as a gangue mineral in ore veins. It is also one of the main minerals in evaporite deposits. ​ Celestine: a soft, sulfate mineral that is often colorless, pale blue, white, or pale yellow. Celestite is another name for it. ​ Epsomite: A frequent mineral found in caves, mines, and salt beds is hydrated magnesium sulfate. Another name for it is Epsom salts.  ​ Alunite: A mineral composed of water, sulfate, potassium, and aluminum Physical Properties Gypsum Barite Anhydrite Celestine Epsomite Alunite White, When pure, Color white Yellow sometimes Light blue White it is greyish colorless Vitreous Vitreous Vitreous Vitreous Vitreous Vitreous to Luster (glassy) to (glassy) to (glassy) to to pearly to silky pearly pearly pearly pearly 3–3.5 on 2–2.5 on 3.5–4 on 1.5–2 on the 3–3.5 on the 3–3.5 on the Hardness the Mohs the Mohs the Mohs Mohs scale Mohs scale Mohs scale scale scale scale Perfect Perfect Perfect Perfect Perfect in cleavage Poor to Cleavage cleavage in cleavage in cleavage in one in three indistinct one direction two directions three directions direction directions Agriculture Gemstone Industrial Fertilizers Manufacturin Cement and Use and & mineral applicatio (used as a g of barium plaster Construction collecting ns minor  source of potassium for agriculture) Uneven to Uneven to Conchoidal to Conchoidal to Uneven to Fibrous or Fracture conchoida subconchoi uneven uneven conchoidal uneven l dal Table 5: Physical properties of Gypsum, Barite, Anhydrite, Celestine, Epsomite and Alunite 6. Halides F. Examples of Halides: This naturally occurring type of sodium chloride is often referred to as rock salt. It is frequently found in sedimentary evaporite deposits and is created by the evaporation of salty lakes and seawater. ​ Halite: Sodium chloride makes up this naturally occurring mineral, which is also referred to as rock salt. It is a cubic, colorless crystal that is frequently used as table salt. ​ Fluorite: a calcium fluoride-based mineral that is colorful. It is frequently found in igneous settings, sedimentary rocks, and hydrothermal veins. It is well-known for its fluorescence under UV light. ​ Sylvite: is a potassium chloride mineral with a more bitter flavor that is similar to halite (NaCl). as arid areas where saline water has evaporated, it develops as evaporite deposits, frequently next to halite. ​ Cryolite: is a mineral that contains sodium aluminum fluoride and was once used extensively in the manufacturing of aluminum. It is uncommon in nature, although Greenland used to have large amounts of it. ​ Carnallite: is usually found in evaporite deposits with other salt minerals like sylvite and halite. It is a hydrated potassium magnesium chloride mineral.  ​ Chlorargyrite: is a silver chloride (AgCl) is the main component of the uncommon silver halide mineral chlorargyrite, sometimes referred to as horn silver. Physical Chlorargy Properties Halite Fluorite Sylvite Cryolite Carnallite rite Transparent or Color White orange White orange Brown white Vitreous Vitreous Vitreous Vitreous to Vitreous to Adamantin Luster (glassy) (glassy) (glassy) greasy greasy e to waxy 2 on the 1–1.5 on 4 on the Mohs 2.5–3 on 2–2.5 on the Mohs the Mohs Hardness scale (relatively the Mohs Mohs scale 2–2.5 on the scale (very scale (very soft) scale (very soft) Mohs scale soft) soft) Perfect cubic Perfect cleavage cleavage Poor or Cleavage in four (breaks Poor to absent absent directions into Perfect cubic cube-like cleavage fragments) None Ceramic & Industrial Gemstone & glass Magnesium application decorative items industry extraction Silver ore s (used in (carved into (used as a (used in the (a fireworks, Use jewelry, flux to production of significant explosives, Food industry figurines, and reduce magnesium secondary and food (used as table ornamental melting metal and source of processing salt and a food objects) temperature compounds) silver ) preservative) ) metal)  Uneven to Subconchoidal Brittle and subconchoi to uneven conchoidal dal Fracture Conchoidal (irregular to (curved or (irregular or (smooth, slightly curved shell-like slightly Sectile (can curved breakage) breakage) curved Brittle and be cut with breakage) breakage) uneven a knife) Table 6: Physical properties of Halite, Fluorite, Sylvite, Cryolite, Carnallite and Chlorargyrite 7. Native Elements G. Examples of Native Elements: Native elements occur in pure forms, such as metals or nonmetals. ​ Gold: a naturally occurring metal that is distinguished by its high density, malleability, and characteristic yellow hue. ​ Silver: a valuable metal with a characteristic shiny sheen that is well-known for its great malleability and conductivity. ​ Copper: Copper is prized for its electrical conductivity, malleability, and resistance to corrosion. It is also known for its characteristic reddish-brown hue.  ​ Diamond: is a kind of carbon that is well known for its remarkable brilliance and toughness. According to the Mohs scale, it is the hardest known natural substance. ​ Graphite: is a naturally occurring element made of carbon that is distinguished by its exceptional electrical conductivity, metallic sheen, and unique slippery feel. ​ Sulfur: is a non-metallic element that is well-known for its characteristic yellow hue and connections to specific chemical reactions and volcanic activity. Physical Gold Silver Copper Diamond Graphite Sulfur Properties  Bright yellow, but can Pure also Metallic white, diamonds are Reddish-brown appear in Metallic often with a shiny perfectly Steel gray to Color with a metallic various yellow or reflective transparent black luster shades appearance and dependin colorless. g on impuritie s Metallic (shiny and Resinous Metallic Adamantine reflective, Metallic (shiny, Metallic (shiny, (shiny, Luster (shiny, (highly brilliant, though not as reflective) reflective) but not reflective) reflective) bright as metallic) metals like silver) ​ 1–2 on the 2.5–3 on the 10 on the Mohs scale 1.5–2.5 Mohs scale Mohs scale 2.5–3 on the Mohs 2.5–3 on the (soft on the Hardness (very soft (hardest scale Mohs scale compared to Mohs compared to known natural other scale other material) minerals) metals) Perfect Perfect in cleavage in Cleavage two None (does not four directions Perfect does not direction Cleavage None break along (forms cleavage in occur in s (forms specific planes) octahedral one direction pure gold. prismatic shapes when crystals) broken)  Electrical wiring (due to its Pencils (used excellent as the writing Industrial electrical Industrial "lead" in Currency & applications, Rubber Use conductivity, cutting tools pencils due Jewelry Jewelry & industry copper is and Jewelry to its ability to Silverware widely used in leave marks electrical wires on paper) and circuits) Conchoid Conchoidal Conchoidal Uneven Uneven al Uneven (irregular (smooth, (breaks with Fracture (irregular (irregular (smooth, breakage) shell-like smooth breakage) breakage) shell-like fracture) curves) fracture) Table 7: Physical properties of Gold, Silver, Copper, Diamonds, Graphite, and Sulfur Questions (Concise Answers) 1. Difference Between Extrusive and Intrusive Igneous Rocks -​ The Magma, or molten rock, cools and crystallizes either inside the crust or at the Earth's surface as a result of volcanic activity to create igneous rocks. The magma from which these rocks cool determines their composition, and the rate at which they cool can affect how they look. For instance, depending on how rapidly or slowly they cool, rocks formed from the same magma can either become granite or rhyolite. The two primary types of igneous rocks are intrusive, which develop when magma cools and solidifies under the crust's surface, and extrusive, which form on the Earth's surface from lava. 2. What is Diagenesis? -​ Diagenesis studies how sediment turns into sedimentary rock by monitoring the crust's mineral dissolution rate and precipitation formation and microbial response patterns within it. Diagenesis is the term used to describe a broad variety of changes that occur in  sediments as they proceed toward becoming sedimentary rocks, including those that occur after they are put down, throughout the rock-forming process, and before to their initial metamorphism. Weathering, the processes that convert various types of rock into sediment, is not included. Early and late stages can be distinguished in diagenesis. Research describes early diagenesis as the interval between deposition and consolidation during which sediment transforms to rock. The initial diagenetic phase incorporates chemical methods through cementation and dissolution/precipitation together with mechanical approaches such as compaction and reworking as well as organic soil development through bioturbation and bacterial processes. The process of rock formation happens during early diagenetic phases. Certain American geologists alongside researchers from Russia restrict the definition of "diagenesis" to its early processes. All transformations which occur after sediment consolidation and before the onset of minimal metamorphism are collectively known as epigenesis or late diagenesis. undefined sedimentary features emerge here during diagenetic processes along with new mineral formation (authigenesis) and low temperature chemical alterations (dolomitization and hydration). 3. How are Sedimentary Rocks Formed? -​ When organic elements and pre-existing rocks build up near the Earth's surface, sedimentary rock formations start. These rocks have layered formations that result in unique mantle patterns that complement arch and mesa characteristics. Natural water sediments that are carried into coastal reservoirs by river systems give rise to sandstone, limestone, and shale. Two processes lead to the formation of stratified rock: first, sediments are compressed, and then they cement and solidify. Clasts from the fragmentation of rocks end up in basins where they finally get compacted. The four basic types of sedimentary rocks are conglomerate (pebbles), siltstone (silt-sized particles), sandstone (sand-sized particles), and shale (clay-sized particles). These can be categorized by the size of their grains. 4. Rate of Weathering and Erosion and the Environment -​ The rate at which rocks weather depends on precipitation totals combined with atmospheric temperature. Warmer climates along with elevated rainfall expedite chemical weathering processes. Rocks at tropical locations deteriorate more rapidly than rocks situated in drier temperature zones because of their abundant rainfall and solar intensity. 5. Process of Metamorphism -​ When protolith rocks endure heat pressure and reactive fluids their composition and texture as well as their internal arrangement undergo changes during metamorphism without reaching the melting point. Inside the Earth's crust, metamorphic processes become primarily active. The combined influence of elevated heat and confining pressure and directional strain modifies protolith composition and structural textures. The directed stress deforms rocks yet recrystallization emerges alongside new mineral structures through a combination of heat and pressure conditions. 6. What is Metamorphic Grade? -​ The degree of metamorphic change a rock undergoes ranges from low grade (minimal change) to high grade (significant change). Low-grade metamorphism occurs under conditions just above those of sedimentary rocks. The progression from slate to phyllite, schist, and ultimately gneiss demonstrates an increase in metamorphic grade. Metamorphic grade reflects the general heat and pressure conditions under which metamorphic rocks form. As temperature and pressure rise, rocks undergo prograde metamorphism, leading to an increase in their metamorphic grade. Types of Rocks (5 Examples Each) 1. Igneous Rocks A.​ Basalt  Description: The dark-colored, fine-grained volcanic rock known as basalt is high in iron and magnesium. It is often dark gray or black in hue and is created when lava cools quickly near the Earth's surface. Uses: Basalt is frequently used in construction as cobblestones, paving stones, and building stones because of its endurance and hardness. Additionally, it is utilized in road materials, tiles, and worktops. It is appropriate for outdoor applications due to its resilience to deterioration. Color: Dark gray Texture: Fine-grained (aphanitic) Hardness: 6–7 (Mohs scale) Density: ~2.8–3.0 g/cm³ Luster: Dull to slightly glassy Porosity: Low (dense, minimal voids) Composition: Rich in iron and magnesium (mafic) B.​ Granite  Description: The main constituents of granite, an igneous rock, are mica, feldspar, and quartz. Depending on its mineral composition, it can range in color from white and gray to black. It is coarse-grained. Uses: Granite's strength and beauty make it a highly prized material in building. It is frequently utilized in facades, monuments, floors, and worktops. It is the perfect option for high-traffic areas and kitchen surfaces because to its durability, heat resistance, and scratch resistance. Color: White Texture: Coarse-grained (phaneritic) Hardness: 6–7 (Mohs scale) Density: ~2.6–2.7 g/cm³ Luster: Dull to slightly shiny Porosity: Very low Composition: High in quartz and feldspar (felsic) C.​ Rhyolite Description: The primary constituents of rhyolite, a fine-grained, light-colored volcanic rock, are feldspar and quartz. It is formed by the gradual cooling of lava and is usually light gray. Uses: Although rhyolite is not as frequently employed in building as other volcanic rocks, it may be used in some architectural applications and as a beautiful stone in landscaping. Because of its porosity, it may be used for decorative reasons but is not appropriate for heavy-duty construction. Color: Light-colored Texture: Fine-grained (aphanitic) Hardness: 6–7 (Mohs scale) Density: ~2.4–2.6 g/cm³ Luster: Dull to glassy Porosity: Can be porous in some varieties Composition: High in silica, similar to granite (felsic) D.​ Diorite Description: Plagioclase feldspar and biotite or hornblende combine to form diorite, an igneous rock with intermediate and coarse grains. It usually has darker mineral inclusions and is light gray to greenish-gray in hue. Uses: Diorite is frequently used in construction as a dimension stone for worktops, flooring, and building facades. It is a wonderful option for ornamental stonework in architecture and landscaping since it is both aesthetically pleasing and long-lasting. Color: Intermediate (gray, black-and-white speckled) Texture: Coarse-grained (phaneritic) Hardness: 6–7 (Mohs scale) Density: ~2.7–3.0 g/cm³ Luster: Dull to slightly shiny  Porosity: Low Composition: Intermediate between basalt and granite (contains feldspar, amphibole, and biotite) E.​ Obsidian Description: Lava cools quickly with little crystal formation to yield obsidian, a naturally occurring volcanic glass. Although it is usually black, depending on the mineral inclusions, it can also appear in dark green, brown, or even rainbow-like colors. Uses: Because of its smooth smoothness and sharpness, obsidian has traditionally been used by ancient civilizations for tools, weaponry, and cutting instruments. These days, it's utilized for ornamental items like artwork, countertops, and jewelry. It also finds specialized usage in medical applications, like as surgical scalpel blades, because of its sharp edges when shattered. Color: Black Texture: Glassy Hardness: 5–6 (Mohs scale) Density: ~2.3–2.6 g/cm³ Luster: Glassy and shiny Porosity: Non-porous (dense) Composition: High silica content, similar to rhyolite (felsic) 2. Sedimentary Rocks A.​ Sandstone Description: Sand-sized mineral particles, mostly feldspar and quartz, make up the majority of sandstone, a sedimentary rock. Depending on the mineral composition, it frequently has tan, yellow, red, brown, or gray hues. Uses: Because of its strength and beauty, sandstone is frequently used in construction for paving, flooring, and building facades. It is also utilized as a raw material to make cement and glass, as well as in sculptures and monuments. Texture: Medium to coarse-grained Color: Light brown Hardness: 6-7 on Mohs scale (depending on composition) Porosity: High (can absorb water) Luster: Dull to matte Cleavage: None, breaks along grain boundaries B.​ Shale Description: Clay minerals and silt-sized particles make up the fine-grained, stratified sedimentary rock known as shale. It usually has a flaky or fissile texture and is gray, black, or brown in appearance. Uses: Shale is a crucial raw material used to make cement, tiles, and bricks. Additionally, it serves as a source rock for the extraction of petroleum and natural gas (shale gas and oil shale) in the oil and gas sector. Texture: Fine-grained, layered (fissile) Color: Mostly gray Hardness: 2-3 on Mohs scale (soft) Porosity: Low to moderate Luster: Dull to earthy Cleavage: Splits into thin layers (fissile)  C.​ Limestone Description: The main component of limestone, a sedimentary rock, is calcium carbonate (CaCO3), which is often found in marine creatures like coral and shell fragments. It is frequently beige, gray, or white, however impurities might cause differences. Uses: For the manufacturing of cement, building stone, and road base, limestone is widely employed in construction. Additionally, it is employed in the steel and glass sectors as well as in agriculture to balance acidic soils. Texture: Fine to coarse-grained Color: Usually white, gray, beige, or yellowish Hardness: 3-4 on Mohs scale (soft to medium) Porosity: Variable (some forms are highly porous) Luster: Dull to slightly pearly Cleavage: None, breaks irregularly  D.​ Conglomerate Description: Round pebbles and bigger rock pieces bound together by sand, silt, or clay make up conglomerate, a coarse-grained sedimentary rock. Depending on the makeup of its particles, it has different colors. Uses: Conglomerate is a decorative stone used in landscaping and building. Additionally, it may be crushed to make materials for roads and concrete. Texture: Coarse-grained (contains rounded pebbles and rock fragments) Color: Brown Hardness: 2-6 on Mohs scale (varies based on cementing material) Porosity: Moderate to high Luster: Dull to earthy Cleavage: None, breaks irregularly around pebbles  E.​ Gypsum Description: Calcium sulfate dihydrate (CaSO₄·2H₂O) is the component of gypsum, a soft, evaporite sedimentary rock. It has a fine-grained texture and is usually colorless, gray, or white. Uses: Cement, plaster, and drywall (plasterboard) are the main products made from gypsum. In addition, it is utilized in medicine to create molds and casts and in agriculture as a soil conditioner. Texture: Fine-grained, soft, often massive or fibrous Color: Colorless Hardness: 2 on Mohs scale (very soft, can be scratched with a fingernail) Porosity: Low to moderate Luster: Pearly to silky Cleavage: Good in one direction (can split into thin sheets) 3. Metamorphic Rocks A.​ Slate Description: Shale or mudstone undergoes low-grade metamorphism to generate slate, a fine-grained, foliated metamorphic rock. It may divide into thin, silky sheets due to its exceptional cleavage. Uses: ​ Roofing tiles ​ Flooring and wall cladding ​ Chalkboards and billiard tables ​ Countertops and landscaping Physical Properties: ​ Color: Gray ​ Texture: Fine-grained, layered (foliated) ​ Hardness: 5–6 (Mohs scale) ​ Density: 2.7–2.9 g/cm³ ​ Luster: Dull to slightly shiny ​ Porosity: Low (water-resistant) B.​ Schist Description: Strong foliation and the presence of visible mineral crystals such as mica, quartz, and feldspar are characteristics of schist, a medium- to coarse-grained metamorphic rock. It arises in situations of moderate to extreme metamorphism. ​ Uses: ​ Decorative stone in construction ​ Road and railroad bed materials ​ Countertops and sculptures Physical Properties: ​ Color: Varies (gray, green, silver, or brown) ​ Texture: Coarse-grained, foliated ​ Hardness: 4–5 (Mohs scale) ​ Density: ~2.7–3.0 g/cm³ ​ Luster: Shiny due to mica content ​ Porosity: Low C.​ Gneiss Description: Light and dark minerals separate to form gneiss, a high-grade metamorphic rock with noticeable banding. It is formed by granite or sedimentary rocks under extreme heat and pressure. Uses: ​ Building stone and countertops ​ Gravestones and monuments ​ Road construction and railway ballast Physical Properties: ​ Color: Banded light and dark minerals (white, gray, pink, black) ​ Texture: Coarse-grained, foliated (banded) ​ Hardness: 6–7 (Mohs scale) ​ Density: 2.6–2.9 g/cm³ ​ Luster: Dull to slightly shiny ​ Porosity: Low  D.​ Marble Description: Heat and pressure cause limestone or dolomite to metamorphose into marble, a non-foliated rock. Because of the mineral impurities, it frequently displays veining and a crystalline structure. Uses: ​ Sculptures and monuments ​ Flooring, countertops, and wall cladding ​ Construction and decorative applications ​ Manufacturing of cement and lime Physical Properties: ​ Color: White ​ Texture: Fine- to coarse-grained, crystalline ​ Hardness: 3–5 (Mohs scale) ​ Density: ~2.6–2.8 g/cm³ ​ Luster: Shiny, polished appearance ​ Porosity: Moderate (can absorb water if unsealed) ​  E.​ Quartzite Description: Under extreme heat and pressure, sandstone transforms into quartzite, a non-foliated metamorphic rock. Its high quartz concentration makes it incredibly durable and weatherproof. ​ Uses: ​ Countertops and flooring ​ Construction material and decorative stone ​ Railway ballast and road aggregate Physical Properties: ​ Color: Reddish ​ Texture: Granular, crystalline, non-foliated ​ Hardness: 7 (Mohs scale) ​ Density: ~2.6–2.8 g/cm³ ​ Luster: Glassy to dull ​ Porosity: Very low (highly resistant to water and weathering)