What is natural stone made from?

08 Apr.,2024

 

NATURAL STONE MAINTENANCE

As the popularity of natural stone installations grows each year, it also drives additional sales opportunities for care and maintenance products. The varieties of stone, the abundance of colors and textures, and the technical characteristics appeal to those seeking a premier building material for renovations, restorations or new construction.

As more and more contractors, designers, architects and homeowners are using the rich look and textures of natural stone in new ways, it has become increasingly important for sales staff, employees, business owners, contractors and homeowners to understand properties and characteristics of natural stone and the basic needs of caring for natural stone after installation.

ALL STONE IS NOT CREATED EQUAL – INSIDE STONE

How stone is created is important to understand, because the composition affects its density, absorption rate, hardness and appearance.

Ultimately, these characteristics determine how natural stone should be maintained to keep its beauty for life. Every region of our world is different and therefore contains unique mineral deposits due to the earth’s formation. All stones vary based on where they are quarried or excavated.

The dimensional stones used in commercial applications fall into one of these categories:

SILICAS / SILICEOUS STONE

Silica is the most common mineral on Earth

  • Generally hard stone
  • Easy to maintain and very durablecarbonates / calcareous Stone
  • Next most common rock-forming group
  • Generally softer, more porous stone than silica
  • Durable, but sensitive to acids (like acid-based cleaners)

IGNEOUS STONES

Created above and below the Earth’s surface, these stones are commonly believed to have solidified from molten rock (called magma) under pressure. Underground, they are formed when magma becomes trapped in small pockets. As these pockets of magma slowly cool, the magma becomes dense igneous rocks. On the surface, when magma appears above the Earth, it is called lava. As the lava quickly cools above ground, different varieties of igneous rocks form.

GRANITE
A coarse-grained siliceous-based stone of even texture composed chiefly of quartz and feldspar minerals it usually contains small quantities of mica or hornblende. Crystallized at depth, granite masses are exposed at the Earth’s surface by crustal movement or by the erosion of overlying rocks.

  • Very hard material
  • Easy to maintain
  • Antimicrobial
  • High density
  • Low porosity, but susceptible to staining

OTHER IGNEOUS STONES
Quartz, Obsidian, Pumas

SEDIMENTARY STONES

Created from a blend of organic materials; small pieces of our Earth that have been eroded, broken down through the action of glaciers, rivers, wind, oceans and plants. These sedimentary pieces include the skeletal remains of living organisms collected to form rock beds (carbonates). These stones have a variety of combinations.

LIMESTONE
Wholly or in large part composed of calcium carbonate, it commonly contains minerals and ancient creatures from seawater. Limestone texture varies from coarse to fine and does not show much graining or crystalline structure. It is ordinarily white but may be colored by impurities, iron oxide making it brown, yellow, or red and carbon making it blue, black, or gray. Varies in hardness, Most susceptible to staining.

TRAVERTINE
A variety of limestone and marble that contains holes formed from heat, pressure and water flowing through the stone. These holes are often filled with foreign materials such as cements or resins during the fabrication process to create a flat, polished surface. It is often beautifully colored and banded as a result of the presence of iron compounds or other (e.g., organic) impurities.

OTHER SEDIMENTARY STONES
Sandstone, Gypsum, Conglomerate

METAMORPHIC STONES

The result of the transformation of a pre-existing rock type, in a process called metamorphism, which means “change in form”. The precursor rock is subjected to extreme heat and pressure causing intense physical and/or chemical change. The precursor rock may be sedimentary rock, igneous rock, or another older metamorphic rock.

Metamorphic rocks make up a large part of the Earth’s crust and are classified by texture and by chemical and mineral assembly. They are also formed by the forces of molten rock into solid rock, particularly at the place of contact between the magma and solid rock, where the temperatures are high.

SLATE
A fine-grained stone formed when sedimentary rocks such as shale are changed by great pressure. Slate splits into wide thin layers. Slate is intermediate in hardness between rocks composed of laminated, often flaky parallel layers of mica and shale.

MARBLE
Marble was once limestone, compacted by heat and pressure that re-crystallized into marble when mineral changes occurred. This produces the colors and veining seen in the stone.

THE DENSITY FACTOR

Hardness is one measure of the strength of stone. The hardness of a stone is relative to the stone’s density. Density can be a factor when considering stone types for a particular project installation.

For example, polished marble can be a beautiful addition to a residential home, but not a shopping mall floor due to the extensive care and maintenance required. The high foot traffic of a mall can eventually dull the surface of polished marble.

MOHS HARDNESS SCALE

Stones hardness can be determined very easily. If a stone can be scratched by a known mineral from the Mohs Hardness Scale list, it is softer than that mineral. If it will scratch another known mineral, then it is harder than that mineral. In this classifi cation, the numbers assigned to objects represent the rank order (1st, 2nd, 3rd etc.) of the entities measured. The variables are called ordinal variables or rank variables. Comparisons of greater and less can be made, in addition to equality and inequality. However, operations such as conventional addition and subtraction are still meaningless.

SCRATCH TEST

Extremely dense stones – typically granites – are not as easily scratched, making them suitable for countertop and floor installations. Lower-density stones, such as the calcite-based stones limestone and travertine, are frequently used in lower traffic areas for aesthetics and beauty.There is an easy, practical way to test the hardness of a stone through a scratch test. You may apply this test on the top or back sides of a piece of stone. (Warning: do not conduct this test on the surface of an installed stone – it may ruin the stone.) Using a box knife steel blade, simply score it across the stone’s surface. Do not apply hard pressure. A stone categorized as granite (quartz/feldspar) will not typically scratch. Because granite has a higher tolerance to scratching, it is widely used on countertops. Marble, travertine, limestone or slate will usually scratch fairly easily with a sharp knife.

FABRICATED & APPLIED TEXTURE

Rough stone blocks are extracted from quarries around the world and then shipped to a fabrication plant. The stone blocks are put through a series of processing steps, depending upon the end product desired. These steps include cutting the block into thin slabs, polishing the slabs, and cutting thin slabs into floor tiles or veneer for building exteriors (curtain). Equipment used in fabricating stone includes diamond wire saws, large blade saws with diamond inserts, and saws durable enough to cut thick slabs for monuments. Computer-controlled machines are capable of easily cutting intricate shapes to satisfy the needs of architects and designers.

The fabrication of the stone will affect its porosity and its appearance. There are many types of textures applied or fabricated to dimensional stone surfaces. This list shows some of the more popularly used fabrication methods applied to stone.

POLISHED
A glossy, highly reflective surface

  • Surface is very smooth and not very porous
  • Polished crystals bring out brilliant colors and grains (400 to 3500 grit to polish stone)
  • Shine comes from the natural reflection of the stone’s crystals
  • Polish can wear away due to heavy foot traffic and improper maintenance

TUMBLED
A slightly rough texture that is achieved by tumbling small pieces of marble, limestone or granite to achieve an old-world/worn appearance

HONED
A flat matte to low sheen gloss

  • Surface is very smooth, but very porous
  • Many more and wider gaps in surface than polished stone
  • Medium density
  • Commonly used in low traffic areas or for aesthetics
  • Colors are not as vibrant as a polished stone

OTHER TEXTURED SURFACES

SAND BLASTED
Pressurized flow of sand and water that results in a matte finish

FLAMED
Rough surface developed through intense heat

BUSH-HAMMERED
Pounding action of hammer develops textured surface. Reduces stone’s color tones

CLEANING FACTS

Acid-based cleaners will slowly damage the appearance of calcium-based stone. The acid creates bigger pores for increased staining potential. It also chemically reacts with the stone causing damage and etching. Some household cleaners can be labeled “tile cleaner” or “all-purpose cleaner”, but can still be very acidic and will damage many types of stone and grout.

ACID CAN DAMAGE STONE

Because carbonates (marble, travertine or limestone) react to acid (acidic cleaners) to create carbon dioxide, the effects to the stone are permanent. The destruction of carbonates shows on the surface of stone as etching. Although the particles of stone cannot be recovered, they can be polished or refinished to match the finish of the stone. CaCO3 + acid = CO2 + H2O + Ca2+ Heavy-duty cleaners and strippers containing alkali are ideal for special circumstances requiring deep cleaning – but should only be used on an occasional basis to remove or strip acrylic finishes, waxes, dirt, oil, and penetrating sealers.

REPAIRING ACID & SURFACE DAMAGE

Aqua Mix® have a range of stone restoration products that are designed to repair and restore marble, travertine & limestone surfaces. Aqua Mix® Reviver® is a user-friendly, highly-effective, ready-mixed paste for polish restoration and maintenance of worn calcium based polished stone. Ideal for large areas. Aqua Mix® Knockdown® is a non-acidic honing powder that removes light surface scratches, moderate acid etching and wear patterns to produce a flat, even and honed finish. It is excellent for safely honing polished marble, limestone or travertine to a smooth honed surface when a honed, unpolished finish is desired.

THE PH BALANCE SCALE

The pH (p=potential of, H=Hydrogen) balance scale measures the acidity or alkalinity of a solution on a scale from 1 to 14. Neutral solutions are rated as a 7. From 7, the number increases with alkalinity and decrease with acidity. Each number from 7 (neutral) is 10x stronger than the previous number.

AQUA MIX CLEANERS

All Aqua Mix cleaners are non-acidic, they safely clean stone surfaces with formulas designed for both routine or heavy-duty cleaning.

MOISTURE VAPOR

The pores and capillaries of stone affect the amount of water that can evaporate through stone – also known as moisture vapor. Moisture vapor is carried from the substrate through the stone to keep the substrate dry– through a process referred to as moisture vapor transmission (MVT). MVT allows the stone to “breathe” naturally, reducing the possibility of mold growth, damage to the substrate, or stone discoloration.

Note: Finishing sealers create a topical finish, covering the stone’s surface, to help repel water and oil. However, based on the job application or improperly-prepared installations, some finishing sealers can trap moisture or inhibit MVT. Most penetrating sealers do not inhibit MVT. Be aware of the type of application, and read all manufacturers’ directions, when selecting a sealer.

HIGH PERFORMANCE SEALERS

  • Prevent a variety of stains – both oil and water-based
  • Allow MVT (Moisture Vapor Transmission)
  • Provides time to react to stains and spills

Premium sealers contain higher quality active ingredients than their more economical counterparts, delivering complete coverage of the gaps in the stone to provide better stain resistance, regardless of porosity and density. Dense stones need smaller sealer molecules to fit into the smaller pores in the surface. Penetrating, water-based sealers offer excellent protection for stone with water as the carrier. Solvent-based sealers protect and penetrate with solvent-based carriers.The choice between a water-based and solvent-based sealer is a matter of intended application. As long as both are premium sealers, they will offer maximum levels of protection.

PENETRATING SEALERS

Active ingredients, or solids, bond with stone and fill in the gaps, or pores, to penetrate the surface. What doesn’t penetrate the surface gets wiped away.

MICROSCOPIC DETAIL

Illustration shows a Penetrating Sealer as if under powerful magnification. Note the various sealing molecules that penetrate and bond to the stone’s surface.

 

 

 

GENERAL RULES FOR MAINTAINING NATURAL STONE & TILE

  1. Routine Daily Maintenance should be done using pH neutral cleaners with a pH in the 7-8 range. These will not harm any tile, stone, grout or sealer used to protect the surface regardless of whether it is a penetrating or coating sealer.
  2. Heavy Duty Cleaning should only be done using alkaline cleaners with a pH in the range of 9-12.
  3. All cleaners require time to work prior to any agitation and removal. This “dwell time” will be longer for heavy duty cleaners. Aqua Mix® cleaners have recommended dwell times on their label instructions.
  4. All cleaning, both routine and especially heavy duty, benefits from some degree of agitation prior to removal.
  5. Extraction of the cleaner residue is by far the best way to maximise cleaner performance. This is best done using a wet and dry vacuum. For routine daily cleaning extraction may be done periodically but on a consistent routine basis. All heavy duty cleaning should incorporate extraction.
  6. Never use acidic or solvent cleaners for routine or heavy duty cleaning. Acid and solvent based cleaners are problem solving compounds that should only be used when a specific issue arises that can ONLY be resolved by use of a problem solving compound. They are not for use on any type of consistent basis.
  7. Remove spills as quickly as possible even on sealed surfaces. Removal of liquid spills is best done by “blotting” the liquid up using a dry white or colour fast absorbent paper towel rather than wiping up the spill. This way the spill is not spread over a greater area. Continue this process until the absorbent towel no longer can absorb any more liquid. Only then will you use an appropriate cleaner to remove any remaining surface contaminant. Applying a cleaner directly on the spill prior to “blotting” can lead to an increase in the size of the contaminated area as well as causing a potentially more aggressive contaminant which can be even harder to remove.

Mar 28, 2023

In a sense, we use “Natural Rocks” and “Natural Stones” terms interchangeably. It is okay at a glance for common folks who know a little about natural stones or stones alone like terms and unaware of its commercial usages or geological perspectives. If you are about to make up your mind for the application of natural stones in your next construction project or idea, we hope the current post may give you a useful insight to know the natural stones and select the right natural stone products using the detailed knowledge.

Remember, natural rocks of all kinds are not suitable for commercial applications like in the construction of residential or commercial projects. A few and selected types of natural rocks give us natural stones to develop commercial products. Thereby, today we will focus on only commercially applicable natural stones.

A Glimpse of the Formation of the Natural Rocks at Geology Perspective

In simple words, natural rocks are a kind of solid lumps of various inorganic minerals and organic substances and exhibiting different properties. 

The formation of rocks began with the cooling process of the Earth and its surfaces. The process is continuing in nature. The formation of natural rocks is a prolonged process, which glued the mass of rocks to gather due to different processes. 

However, the Geologists give us a glimpse of those highly complicated processes into three simple terms.

  1. Igneous formation of rocks

  2. Metamorphism of rock formation

  3. Sedimentation of rock formation 

Let’s get a brief review of each process.

Igneous Formation:

The igneous rock formation is the result of volcanic activity on the Earth. Hot magma/lava is cooling after an eruption. Various factors act on the solidification process and wonderful igneous rocks. 

A comprehensive list is given below, showing different types of igneous rocks, and you can know more about all in detail in our post.

Granites and Basalts are commercially accepted igneous rocks and abundantly used in various construction projects as well as in different industries.

Sedimentary Formation:

Inorganic minerals and organic substances are transporting through various means like water and wind from one place to another and depositing in layers. Over time these layers get solidifications and transforming into solid rocks. Based on the deposition or sedimentation process, these rocks are termed as sedimentary rocks.

The following are a few names to mention here.

Limestone, Sandstone, and Travertine are commercially recognized species of sedimentary rocks. 

Metamorphic Formation:

When igneous or sedimentary rocks are passing through the metamorphic process under the influences mainly heat and pressure like physical factors compaction occurs along with physical and chemical changes in the structure of those rocks. The resulting rocks are called metamorphic rocks with altogether different properties and looks.

Marble, Quartzite, and Slate have known types of metamorphic rocks in the industry. Quartzites are forming at the deepest layers of earth surface white marble at the mid-level, and slates are almost near the top surface.

Therefore, quartzites are the sturdiest stones, while marbles are softer. Slates are fragile due to less compaction and unique layering patterns. Quartzite and slates are rich in silica (Quartz) whereas, marble is rich in lime and assimilation of organic substances including fossils. 

The journey of Natural Stones from Mining to Factory 

Natural rocks need careful excavation or mining processes to market-ready. Experts identify the sites and use heavy machinery to extract giant blocks of natural rocks. Modern digging, rock cutting, and pulling technologies have made the process easy as well as fast for stone miners. 

Cutting:

Cutting the large size of stone blocks with diamond cutters is easy. 

Heavy cranes can lift those large blocks and load on suitable vehicles to transport. 

Transportation

:

Heavy-duty vehicles can carry heavy size blocks safely on odd and unstructured roads from mines located in the deep regions to processing units/factories.

Fragmentation:

Large stone blocks need further cutting to get commercially viable stone sizes in standard or custom dimensions. It takes place in the processing units with sophisticated cutting and segregation tools.

Different Types of Stone Cuts:

We can get cross-cut and vein-cut slices of the natural rocks. When we cut across the layers or strata of the natural rocks, we can get large swatches of color variations with cross-cut.

Similarly, the vein cut is making slices of stone along with the layers and exposing veining patterns on the surfaces of stone slabs or tiles.

Different Types of Stone Surface Finishes

After cutting of the natural rocks into dimensional natural stones, it needs surface treatments or surface finishing process to be ready for the installations on the interior and exterior sites. You can get details of surface textures of stones in one of our posts.

Surface finishing is exposing or creating unique and natural surface textures. There are different types of surface finishing process found in the industry, such as:

Natural finishing

Sawn Finish

Riven Finish

It yields sawn stone surface texture and riven stone surface textures.

Chemical finishing 

Acid Wash Surface Texture & Epoxy Surface Texture:

It gives us acid wash surface texture and epoxy surface texture using acids and epoxy resin, respectively.

Types of Natural Stones Used in Commercial Applications 

We know all kinds of natural rocks are not useful in the preparation of commercially applicable natural stone products. Therefore, we are going to list highly used stone types only here.

There are two kinds of stone categories found commercially viable based on their content, strength, hardness, durability, and other standard properties.

  • Siliceous stones

    , which are rich in silica or quartz particles

  • Calcareous stones

    , which have calcium components predominantly.

Siliceous Stones:

Quartzite

It is a metamorphic siliceous stone type. The sturdiest product with good strength, color & pattern variation to beautify your spaces, mostly kitchen countertops, and cabinet-tops. 

Granite 

It is an igneous type of rock with high silica and awesome strength. Found abundantly so common in use. Ideal for countertops, floors, and various exterior applications.

Slate

It is a metamorphic type of rock & made of volcanic ash and clay particles. It has a peculiar property called fissility. It is great for roof construction and exterior paving.

Sandstone

It is a sedimentary kind of stone with sand as the chief component. It is a sturdy and durable natural stone type. So, highly used as a structural element in the past. At present, it is ideal for flooring and wall cladding.

Calcareous Stones:

Limestone

It is a sedimentary type of stone mainly made of calcites. It mostly found as paving material for outdoor applications. It has other industrial applications like as raw material in the preparation of lime and cement. 

Marble

It is the most used stone type on the planet. It is a metamorphic rock with rich in calcites and other stuff to make it gorgeous in look. For interior applications, it is ideal for flooring and wall cladding.

Travertine

It calcareous and sedimentary type of natural stone. It forms from precipitation of calcites present in hot mineral springs and other water resources. It is good for flooring on swimming decks and patio paving.

Applications of Natural Stones in the Construction Industry

Natural stones can use almost in all types of applications in the construction industry. Let’s see some major applications.

Interior Flooring

Marbles like natural stones are the prime choice for neat and attractive flooring with natural beauty. 

Exterior Patio Paving

You can decorate your backyard and garden patios with natural stones. We have enough choices for stone types and textures.

Interior Wall Cladding

Natural stones are superb in wall cladding for interior spaces like bathrooms.

Exterior Wall Cladding

Exterior façade, stairs, and retaining wall cladding with natural stones make the stunning appearance of your property.

Driveway 

The driveway is an essential utility and useful component to beautify your exterior. Natural stones have enough varieties to make it appealing for your visitors.

Walking Path 

We can make walking a pleasing experience by using natural stones. Stone slabs are available for narrow to wide path creation with desired patterns and matching colors.

Stepping Stones

Elegancy in your garden or outdoor landscape comes with carefully & artfully laid stepping stones using the natural stones. Of course, stones assimilate seamlessly in the landscape ambiance thanks to the natural beauty of stones.

Window Sill

When you are looking for aesthetic appeal to the interior as well as exterior look simultaneously, windowsills and headers like minor structural elements allow you to do so. Go to natural stones to create classic and stunning looks.

Pool Deck

A swimming pool is a unique place to amalgamate natural beauty with utility. Natural stones have both and suit as the best material for pool deck flooring as well as in rests of components of the pool.

Fountain

The fountain is an artistic expression and natural stones have enough properties to meet those needs beautifully to beautify your landscape. Marble is an ideal stone type with the desired softness.

Water Feature

A stone water feature is the best way to bring natural agility in your landscape design. Raw stones, aggregates, and slabs are providing the right combinations to make it dazzling.

Fire Feature

Most of the standard stones withstand to heat and useful in the construction of fire features to get warmth along with relaxations during cold days or nights. You can make rounded sitting benches from stones.

Who Could Be Your Natural Stone Provider?

World of Stones USA in Maryland is an ideal stone supplier and distributor with a wide network across the country and globe. The right consultancy makes your shopping experience elegant and reliable. Huge inventory is offering enough choices to make for your spaces in bespoke ways. Competitive rates, along with useful services, are plus points to establish long-term relationships.

Would you like to run an online inquiry and check the difference we make?

What is natural stone made from?

How Natural Stone is Made – All You Need to Know