Granite is formed by igneous rock. It is a steel-hard crystalline stone. It is originally formed by feldspar and quartz and is mixed with one or more black minerals. It is arranged flat in structure.

Granite is primarily composed of quartz, feldspar, and mica. Feldspar accounts for 40%-60% and quartz 20%-40%. Its color depends on the type and amount of these components. Granite is a fully crystalline rock. High-quality granite features fine and uniform grains, a dense structure, a high quartz content, and a bright feldspar sheen.

Granite has a high silica content and is classified as acidic. Some granites contain trace amounts of radioactive elements and should not be used indoors. However, granite has a dense structure, a hard texture, and is resistant to acids, alkalis, and weathering, making it suitable for long-term outdoor use.

Huayan is a unique material, and its physical characteristics are mainly as follows:

Porosity/Permeability: The physical permeability of granite is almost negligible, ranging from 0.2% to 4%.

Thermal stability: Granite has high thermal stability and will not change due to changes in external temperature. Granite has a high density and will not change due to changes in temperature and air composition. Granite has strong corrosion resistance and is therefore widely used in the storage of chemical corrosives.

Ductility: The ductility coefficient of granite ranges from 4.7x10-6 to 9.0x10-6 (inch x inch). 

Color: The color and texture of granite are highly consistent.

Hardness: Granite is the hardest building material, and its extreme hardness also makes it very wear-resistant.

Composition: Granite is primarily composed of quartz, orthoclase, and microcline. The most primitive granite is primarily composed of the following three components: feldspar, quartz, and biotite. The proportions of each component are generally determined by color and material, but generally feldspar accounts for 65%-90%, quartz 10%-60%, and biotite 10%-15%.

Granite is mainly composed of feldspar, quartz, and biotite, but it is also accompanied by the presence of other minerals. The main proportions of various minerals are as follows:

Granite has many types and can be classified in many ways due to its complex composition and diverse formation conditions.

It is divided into black granite, muscovite granite, hornblende granite, two-mica granite, etc.

It can be divided into fine-grained granite, medium-grained granite, coarse-grained granite, porphyritic granite, porphyritic-like granite, geode granite and gneissic granite.

It can be divided into cassiterite granite, niobite granite, beryllium granite, lepidolite granite, tourmaline granite, etc. Common automorphisms include feldsparization, greisenization, and tourmalineization.

Granite has a dense structure, high compressive strength, low water absorption, high surface hardness, good chemical stability, and strong durability, but poor fire resistance.

Granite has a granular structure of fine, medium, or coarse grains, or a porphyritic structure. Its grains are uniform and fine, with small gaps (porosity is generally 0.3% to 0.7%), low water absorption (water absorption is generally 0.15% to 0.46%), and good frost resistance.

Granite is known for its high hardness, with a Mohs hardness of around 6. Its density ranges from 2.63 g/cm³ to 2.75 g/cm³, and its compressive strength ranges from 100 to 300 MPa, with fine-grained granite reaching over 300 MPa. Its flexural strength is generally between 10 and 30 MPa. Granite is often found in the form of bedrock, stocks, and blocks, and is controlled by regional tectonic shifts. It is generally large and widely distributed, making it easy to mine and produce large pieces. Its well-developed joints also facilitate the extraction of regularly shaped rocks.

Granite has a high yield rate, is amenable to various processing methods, and offers excellent slab splicing properties. Furthermore, it resists weathering and can be used as outdoor decorative stone. Granite has a uniform texture and, while primarily pale in color, also offers a wide variety of colors, including red, white, yellow, green, black, purple, brown, beige, and blue. Its color variation is relatively minimal, making it suitable for large-scale applications.

Granite is beautiful, durable and very hard. In ancient times, if there were advanced mining and processing equipment and technology, it would definitely be more popular than marble.

Granite often contains other minerals such as amphibole and mica, resulting in a variety of colors including brown, green, red and the common black.

Because it crystallizes slowly, its crystals intertwine like a Rubik's Cube, making it incredibly hard. It's as durable as a house, resisting chipping, scratching, and high temperatures. Regardless of color or finish, with common sense care, it won't fade or darken. It's virtually impervious to contamination, achieving a high gloss after polishing, and virtually resistant to weather-related impurities.

Granite is typically mined using wire rope sawing. Newer techniques, such as dense drilling and flame spraying, have emerged. Flame spraying produces clean cuts, no hidden defects, and high production efficiency. After roughing, the mined stone is called rough material. It is then manually drilled and chiseled or machine sawed to produce blocks or slabs of the desired size. Milling machines or lathes are used to form cylindrical or curved shapes. Finally, coarse and fine rock-like grains are manually chiseled, or machine-ground and polished to a crystal-clear finish.

Granite is environmentally friendly. Synthetic materials often leave unpleasant or even toxic byproducts and need to be replaced several times during the life of the building (each time with associated disposal issues). Granite doesn't need to be replaced because it's incredibly durable.

In addition, granite is very practical and can be made into a variety of surfaces - polished, matte, fine-ground, flamed, water-jet treated and sandblasted. Because granite often contains radioactive substances, when using granite, its radiation level needs to be measured and then its use occasion needs to be confirmed.

Decorative granite polished slabs are as bright as a mirror and have a gorgeous and noble decorative effect. Common types of granite polished slabs include:

Red series: Sichuan red, asbestos red, Cenxi red, tiger skin red, cherry red, Pinggu red, azalea red, rose red, Guifei red, Luqing red, Lianzhou red, etc.

Yellow-red series: Cenxi orange red, Dongliu flesh red, Lianzhou light red, Xingyang peach red, Xingyang orange red, light red small flowers, cherry red, coral flower, tiger skin yellow, etc.

White flower series: Baishihua, Baihujian, black and white flower, sesame white, white flower, Lingnan white flower, Jinan white flower, Sichuan white flower, etc.

Black series: light blue black, pure black, sesame black, Sichuan black, Yantai black, Shenyang black, Changchun black, etc.

Cyan series: sesame green, rice green, fine linen green, Jinan green, bamboo leaf green, chrysanthemum green, blue and white, reed flower green, Nanxiong green, Panxiong blue, etc.

Imported granite: Golden Diamond, South African Red, Fantasy Green, Kashmir Gold, Small Emerald Red, Dark Green Linen, American Gray Linen, Fantasy Red, Indian Red, British Brown, etc.

Natural granite products can be divided into the following categories according to different processing methods:

Axe-cut stone: The surface of the stone is hand-cut with an axe, resulting in a rough surface with regular stripes. The surface texture is rough and is used for non-slip floors, steps, bases, etc.

Machine-planed boards: The surface of the stone is mechanically planed, the surface is flat, and there are parallel planing lines. It is used for similar purposes to chopped axe boards, but the surface texture is finer.

Roughly ground slabs: The surface of the stone is roughly ground, smooth and matte, and is mainly used for walls, columns, steps, bases, etc. that require soft light effects.

Polished slabs: The surface of the stone has been finely ground and polished, and the surface is flat and bright. The granite crystal structure has clear texture and the color is gorgeous. It is used for walls, floors and columns that require a high-gloss and smooth surface effect.

Granite is used according to its grain size: fine grains can be polished or carved to be used as decorative panels or works of art;

Medium-sized granite is often used in the construction of bridge piers, arches, dams, harbors, plinths, foundations, and road surfaces. Coarse-grained granite is rolled into crushed stone, which is an excellent aggregate for concrete. Because granite is acid-resistant, it is also used as acid-resistant linings and containers in chemical and metallurgical production.

1. Check whether the stone provided is natural stone and whether its material properties meet or exceed those of natural granite (JB/T 7974-2001).

2. Quality inspection requirements: The specified value or allowable deviation of the overall dimensions is ≤±1mm in length, ±1mm in width and thickness, the specified value or allowable deviation of the surface flatness is ≤0.5mm, and the specified value or allowable deviation of the diagonal is ≤0.5mm.

3. Whether the appearance quality of the granite platform is of high quality, and whether the color, color difference and pattern of the block material are harmonious and uniform.

4. Check whether there are any external defects on the platform surface, such as missing edges, missing corners, cracks, color spots, color lines, and pits.

5. Whether the platform surface is painted with six-sided stone protective coating to ensure the waterproof and anti-fouling properties of the stone.

6. Whether the stone has passed the relevant inspections of the National Stone Quality Monitoring Center, including physical properties, radioactivity, freeze-thaw resistance, etc., and has relevant inspection reports.

Granite is a widely distributed rock found in many countries around the world. 9% of the land area (approximately 800,000 square kilometers) is made up of granite.

The following are the different types of granite and where they are found:

Jade Qilin Origin - Vietnam

Palace Stone, Indian Flower, Coffee Pearl, Monte Carlo, Indian Black Gold Origin - India

Shanxi Black (Shanxi), Xuanwu Black (Fujian), Taishan Red (Shandong), Cenxi Red (Guangxi), Dahongmei (Hainan Island), Red (Sichuan), Black King Kong (Inner Mongolia), Bean Green (Jiangxi), Green Background and Green Flowers (Anhui), Xuelimei (Henan) Origin -

Autumn Brown Origin--Canada

American White Hemp and Texas Red Origin - United States

Brazil

Swedish mahogany stone origin - Sweden

Travertine Origin--Italy

Blue Pearl Origin--Norway

Cat Gray Stone Origin - Portugal

Rose Red Origin--Spain

Small Cui Red, Eagle Red, Carmen Red, Green Mabao, and Juhuagang are produced in Finland.

South African Red and Forest Blue Origin - South Africa

Granite mineral resources are also extremely rich, with large reserves and a wide variety of varieties. According to survey data, there are more than 100 varieties of natural granite patterns and colors. Granite used for architectural decoration is named after its pattern, color characteristics and the origin of the raw materials.

Among them, the better ones include chrysanthemum green, snowflake green, and Yunlimei from Henan Jiangshi, Jinan green from Shandong Jinan, Shimian from Sichuan Shimian, bean green from Shanggao, Jiangxi, Zhongshan jade from Zhongshan, Guangdong, Guifei red, orange, pockmarked white, green and black flower, yellow and black flower from Lingqiu, Shanxi.

Granite is sourced from high-quality underground rock layers. After millions of years of natural aging, its shape is extremely stable, and there is no need to worry about deformation due to normal temperature differences. The granite platform is made of granite materials that have undergone rigorous physical testing and selection, resulting in fine crystals and a hard texture.

Because granite is a non-metallic material, it exhibits no magnetic properties and exhibits no plastic deformation. Granite platforms are highly hard, resulting in excellent precision retention. However, since granite often contains radioactive substances, its radiation level must be measured before use, prior to confirming its intended application.

Granite resources are rich and varied, and have been widely used in civil engineering since ancient times. More than 40 types of granite are used as facing stones, including Jinan Green. The main production areas are: Mount Tai and Mount Lao in Shandong, Mount Hua in Shaanxi, Xishan in Beijing, and southern Fujian.

Newly laid granite floors are not suitable for base wax and surface wax: Why newly laid granite floors are not suitable for base wax and surface wax? We can draw a conclusion by comparing it with marble.

The surface of marble, whether new or old, is composed of calcium carbonate crystals with large particles and therefore large pores. Even after meticulous polishing, the uneven interface can still be seen under a microscope. These tiny pores are the advantages for drop wax: when the base wax is applied, the base wax has a small molecular weight and strong permeability, coupled with capillary action, the base wax is quickly adsorbed on the marble surface to form a film. When the moisture in the base wax completely evaporates, the adsorption force is even greater. This adsorption force is crucial. It is used to counteract the force exerted on its surface due to people walking and dragging objects, so as to prevent the wax surface from leaving the ground.

As for the newly laid granite floor, its main components are crystals of quartz, mica, and feldspar, which have high density and extremely high hardness. In addition, manual polishing makes the granite surface almost non-porous. Therefore, when waxing, the base wax cannot penetrate, there is no capillary action, and of course there is no or only very weak adsorption force. Such a wax surface is easy to fall off when people walk on it, making the waxing work futile.

In view of this situation, for newly laid granite, it is only necessary to spray it with cleaning wax within six months to one year after laying to prevent stains from penetrating into the granite and maintain its surface brightness. Due to the different directions and strengths of people passing through every day, the degree of wear on the granite surface is also different. After a period of time,

Limestone, also known as limestone, is a carbonate rock primarily composed of calcite. It sometimes contains dolomite, clay minerals, and detrital minerals. It can be gray, off-white, gray-black, yellow, light red, or brown-red. It is generally not very hard and reacts violently with dilute hydrochloric acid.

Limestone is primarily formed in shallow marine environments. Based on its origin, limestone can be divided into granular limestone (formed by water transport and sedimentation); bioskeletal limestone; and chemical and biochemical limestone. Based on its structural structure, it can be further subdivided into bamboo-leaf limestone, spherical limestone, and massive limestone. Limestone's primary chemical component is calcium carbonate, which is easily soluble. Therefore, limestone regions often form stone forests and caves, known as karst topography.

Limestone is the main raw material for burning lime and cement, and is a flux for iron and steel making.

Biochemically generated shale often contains abundant organic debris. Limestone generally contains some dolomite and clay minerals. When the clay mineral content reaches 25% to 50%, it is called argillaceous rock. When the dolomite content reaches 25% to 50%, it is called dolomitic limestone. Limestone is widely distributed, has a uniform lithology, and is easy to mine and process, making it a widely used building material.

The main component of limestone is calcium carbonate, which can dissolve in water containing carbon dioxide. Generally speaking, one liter of water containing carbon dioxide can dissolve about 50 mg of calcium carbonate.

Geologists investigating the Guilin region have discovered that the water there dissolves and erodes a layer of limestone approximately as thin as a fingernail each year. While this amount of erosion may seem small, the Earth's history is incredibly long. For example, the Quaternary Period, the most recent geological period, spans approximately three million years.

Even at such a slow rate of dissolution, 900 meters can be eroded in 3 million years! Meanwhile, Guilin's isolated peaks are only a few hundred meters high, and the most common karst caves are only a few dozen meters high. However, this type of landform cannot be formed anywhere with limestone. It requires large, thick, and geologically pure limestone, along with a warm and humid climate, to develop such a perfect landform and create such beautiful natural scenery.

Limestone is one of the most widely distributed minerals in the Earth's crust. Based on its depositional area, limestone can be divided into marine and terrestrial deposits, with the former being the most common. Based on its genesis, limestone can be divided into three types: biogenic, chemical, and secondary. Based on the different components contained in the ore, limestone can be divided into siliceous, clayey, and dolomitic limestones.

Resource Distribution: Limestone mineral resources are abundant, with over 800 deposits used for cement, solvents, and chemicals. Limestone is produced throughout China, and can be sourced locally near industrial zones in all provinces, municipalities, and autonomous regions.

Limestone deposits have been deposited in every geological era and are distributed throughout every stage of geological tectonic development. However, high-quality, large-scale limestone deposits are often found in specific strata. For example, the Middle Ordovician Majiagou Formation limestone in Northeast China and North China is an extremely important stratum for cement production. Carboniferous, Permian, and Triassic limestones are commonly used in Central South, East China, and Southwest China, while Silurian and Devonian limestones are generally used in Northwest China and Tibet. The Ordovician limestone in East China, Northwest China, and the middle and lower reaches of the Yangtze River is also an important stratum for cement production.

The mineral composition of limestone is primarily calcite, accompanied by dolomite, magnesite, and other carbonate minerals, as well as some other impurities. Magnesium appears as white limestone and magnesite, silicon oxide appears as free quartz, chalcedony and opal are distributed within the rock, and aluminum oxide combines with silicon oxide to form aluminum silicates (clay, feldspar, and mica).

Iron compounds exist in the form of carbonates (magnesite), pyrite (pyrite), free oxides (magnetite, hematite) and hydroxides (hydrous goethite); in addition, there is glauconite. Some types of limestone also contain organic matter such as coal and asphalt, sulfates such as gypsum and anhydrite, as well as compounds of phosphorus and calcium, alkali metal compounds, and compounds of strontium, barium, manganese, titanium, fluorine, etc., but the content is very low.

Limestone has excellent workability, polishability, and excellent cementing properties. It is insoluble in water but readily soluble in saturated sulfuric acid. It reacts with various strong acids to form corresponding calcium salts, releasing CO2. When calcined to temperatures above 900°C (generally 1000-1300°C), limestone decomposes into lime (CaO), releasing CO2. Quicklime deliquesces upon contact with water, immediately forming slaked lime [Ca(OH)2]. Slaked lime can be dissolved in water to form a slurry and readily hardens in air.

The properties of limestone can be simply understood as the chemical properties of calcium carbonate.

A carbonate rock primarily composed of calcite. Limestone is a sedimentary rock. It sometimes contains dolomite, clay minerals, and detrital minerals. It can range in color from gray, off-white, gray-black, yellow, light red, to brown-red. It is generally not very hard and reacts violently with dilute hydrochloric acid. Its structure is complex, with both a detrital and granular structure.

The clastic structure is mostly composed of particles, a micrite matrix, and spar cement. Particles, also known as granular debris, mainly include intraclasts, bioclasts, and oolitic particles. The micrite matrix is ​​a sludge composed of calcium carbonate fines or crystals, most of which are smaller than 0.05 mm. The spar cement is a chemical precipitate that fills the pores between rock particles and consists of calcite crystals larger than 0.01 mm in diameter. The grain structure is composed of crystalline particles precipitated by chemical and biochemical processes.

Lime has excellent properties such as thermal conductivity, firmness, water absorption, air impermeability, sound insulation, polishability, good bonding properties and processability. It can be used directly as a raw ore or further processed for application.

Limestone is an important industrial raw material in metallurgy, building materials, chemicals, light industry, construction, agriculture and other special industrial sectors. With the development of the steel and cement industries, the importance of limestone will be further enhanced.

Limestone has a wide range of uses and is an essential raw material in various sectors of the national economy and in people's lives. It is mainly used for:

(1) Used in the construction industry to produce cement and burn lime;

(2) Used as flux in the metallurgical industry;

(3) Used in the chemical industry to produce alkali, bleaching powder and fertilizers;

(4) Used as a clarifier in the food industry;

(5) Used in agriculture to improve soil;

(6) Used as filler in the plastics industry;

(7) Widely used in the coatings industry to make various architectural coatings;

(8) Used as alkaline filler in papermaking industry;

(9) Used as basic filler for rubber in the rubber industry;

(10) Used as an adsorbent in the environmental protection industry.

Heavy calcium carbonate is a product made from natural calcite, limestone and chalk, which is mechanically crushed to a certain fineness. There are two production methods: dry and wet. The wet grinding process, which has made significant progress abroad, is still a blank in China.

In the process of producing light calcium carbonate from limestone, there is still a large gap between the particle size and crystal shape control of light calcium carbonate products and those of foreign countries. Therefore, it is necessary to further develop the deep processing industry of limestone, expand its application areas, strengthen its comprehensive utilization, increase product value and improve economic benefits.

Limestone is an important industrial raw material for metallurgy, building materials, chemical industry, light industry, agriculture and other sectors. With the development of steel and cement industries, the demand for limestone will further increase.

Currently, cement production is enormous, requiring over 100 billion tons of limestone to be mined annually for cement production. It is projected that by the year 2000, national cement production will reach 300 million tons, requiring even greater quantities of limestone to be mined as raw material. Furthermore, the metallurgical and chemical industries also have a significant demand for limestone.

Therefore, the limestone industry has broad production and development prospects. In order to make limestone products have greater added value, developing deep-processing limestone products is also a future development direction.

Sandstone is a sedimentary rock composed mainly of sand grains, with the sand content exceeding 50%. Most sandstones are composed of quartz or feldspar, which are the most common components of the Earth's crust.

Sandstone, like sand, can be any color, with brown, yellow, red, gray, and white being the most common. Sandstone cliffs are common on Earth.

Sandstone is formed by debris deposition, which is different from biological deposition such as coal and chemical deposition such as gypsum and jade. The debris can be other rocks or certain mineral crystals. The material that cements these debris can be calcite, clay or silica. The particle size of the debris is between 0.1 and 2 mm. If the particle size of the debris is too small, it will form schist or shale. If it is too large, it will form conglomerate or breccia.

Sandstone containing iron oxide stripes The formation of sandstone is divided into two stages. First, the sand grains are deposited layer by layer, which may be caused by water or atmospheric transport; then, under the action of pressure, they are cemented together by calcium carbonate or silica leached from above. The iron, silicon, manganese and other elements contained in the sandstone will cause the sandstone to have different colors.

Due to differences in sedimentary environments, various sandstones have different joints, grain sizes, colors and properties, and are mainly divided into two categories: terrestrial sediments and marine sediments.

With the exception of biogenic structures, almost all sedimentary rock structures can be found in sandstone. Intra- and inter-laminar structures are the most obvious indicators of the type and strength of the fluids that transported the sediments. For example, cross-bedding is a hallmark of paleocurrents, and different types of grain-sequenced bedding are indicators of traction currents and turbidity currents.

Sandstone is divided into coarse-grained sandstone (2-1mm), coarse-grained sandstone (1-0.5mm), medium-grained sandstone (0.5-0.25mm), fine-grained sandstone (0.25-0.125mm), and fine-grained sandstone (0.125-0.0625mm) according to the diameter of the sand particles. Among the above sandstones, the corresponding particle size content should be above 50%.

Classification by rock (mineral) type: quartz sandstone (quartz and various siliceous rock fragments account for more than 95% of the total sand-grade rock fragments) and quartz greywacke, feldspar sandstone (the debris components are mainly quartz and feldspar, of which the quartz content is less than 75% and the feldspar content exceeds 18.75%) and feldspar greywacke, lithic sandstone (the quartz content in the debris is less than 75%, the rock fragment content is generally greater than 18.755, and the rock fragment/feldspar ratio is greater than 3) and lithic greywacke.

The main types of sandstone are quartz sandstone, feldspathic sandstone and lithic sandstone.

Quartz and siliceous rock fragments account for over 95% of the total sand-grade debris, with little or no feldspar, rock fragments, or heavy minerals. The debris particles are often dominated by single-crystal quartz, with good roundness and sorting, and the highest compositional and structural maturity.

It has a low matrix content and is supported by particles. When the matrix content is > 15%, it is called quartz greywacke. Quartz greywacke primarily forms in stable tectonic environments with quasi-plain terrain. The parent rock undergoes long-term weathering and denudation, and the resulting products are mostly slowly deposited in marine environments (such as beaches) under the intense selection and repeated abrasion of waves and currents. It often coexists with carbonate deposits, forming the quartz sandstone-marine carbonate formation, such as the Upper Precambrian in the northern half of the North China Platform.

Feldspar fragments account for over 25% of the total sand-grade fragments. Quartz content is <75%, and may contain significant amounts of mica and heavy minerals. The cement is primarily calcareous and ferrous, often containing a clay matrix. When the matrix exceeds 15%, it is classified as feldspar greywacke.

The clastic particles are generally well-sorted and of medium roundness. Arkose sandstone often appears pale yellow, fleshy pink, or greenish-gray. Based on the conditions of its formation, arkose sandstone can be divided into three categories: tectonic arkose sandstone, basement arkose sandstone, and climatic arkose sandstone. Arkose sandstone is generally formed in areas of intense tectonic movement, where the parent rock is granite or granite gneiss, in dry, cold climates, and where physical weathering is predominant, resulting in intense erosion and rapid accumulation.

Most are continental deposits, with marine deposits being rare. They often accumulate in piedmont or intermontane basins. Many feldspathic sandstones have been found to form within continental rifts. The Sinian System in Tangshan, Hebei, contains feldspathic sandstones containing over 50% feldspar.

Rock fragments account for over 25% of the total sand-grade debris. Quartz content is <75%, and may contain a small amount of feldspar (<10%). Heavy minerals are high and complex in nature. Cement is often siliceous and carbonate, often containing impurities.

When the matrix content is > 15%, it is classified as lithic greywacke. The roundness and sorting of the clastic particles range from medium to poor. They are often light gray, gray-green, or dark gray. The composition of the lithic debris is closely related to the properties of the parent rock in the source area and can be further divided into rock types based on its composition.

Lithic sandstone is a type of sandstone with low compositional and structural maturity, mainly formed in piedmont or intermontane depressions in areas with strong tectonic changes.

The chemical composition of sandstone varies greatly, depending on the composition of the debris and fill. The chemical composition of sandstone is mainly SiO2 and Al2O3, and the SiO2/Al2O3 ratio is the hallmark of mature and immature sandstone.

Quartz is the primary mineral fragment in sandstone. It is the most stable under surface conditions and is the main component of most sandstones. It is often used as an indicator of parent rock. The content of feldspar in sandstone is second only to quartz, and in some cases exceeds quartz.

It is generally believed that the content of feldspar debris is affected by climate, the intensity of crustal movement, and the properties of the parent rock. Rock fragments are a direct indicator of the parent rock. In sandstone, they are mostly volcanic debris or fine-grained, relatively stable sedimentary and metamorphic debris.

Heavy minerals are a set of minerals in sandstone with a specific gravity greater than 2.87. Their content is generally less than 1%. The typological characteristics and assemblage of heavy minerals (combined with the assemblage of light minerals) are valuable for reconstructing parent rock types, conducting stratigraphic correlations, and tracing terrigenous sources.

It includes chemical cements and clastic matrix. Silicity and carbonates dominate the cements. Siliceous cements are generally secondary, overgrown quartz, with chalcedony and opal being less common. Calcite is the most common carbonate cement, while dolomite and siderite are less common.

Siliceous cements are more common in older sandstones, while carbonate cements are more common in younger sandstones from the Mesozoic and later periods. This is generally believed to be due to the different stabilities of the two types of cements, or to the ease with which carbonate cements are leached away.