- This question actually includes four chunks of content. Here we have 4 kinds of stone material. Here we answer the following questions for each material, “what’s granite/sandstone/ travertine? What character does the material have and where does it often to be used for?”
- The idea is to show different features of each type stone in decoration or sculpture, like: density, hardness, porosity, colour, patterns, etc.
What is marble?
Marble is a type of metamorphic rock derived from the recrystallization of sedimentary limestone exposed to intense heat and pressure. This process occurs to limestone deep within the earth and is associated with tectonic activity.
Differences in the duration, heat, pressure, and other impurities present during metamorphism can lead to the production of marble types with a variety of structural and chemical compositions. One thing to introduce is that these properties makes marble the best material to build a stone bathtub.
Marble is primarily composed of calcium carbonate (CaCO3) in the form of calcite that is both structurally homogenous and of a fine grained, granular texture.
Marble usually contains other additional chemical impurities (e.g., metal oxides, silicates) which can lead the naturally pure white marble to gain unique patterning (e.g., veins, branches) and overall color variations across the color spectrum (common colors include: white, grey, pink, yellow, grey, brown, green, blue, black).
These color and patterning variations have been considered to be more abundant than other comparable natural materials (e.g., sandstone, granite, sandstone, travertine). This ability of marble to be present in so many unique and easily identifiable patterns allows it to stand out within the design world.
The color and patterning variations makes marble a perfect material choice for statues, garden fountains, or any decoration materials. Since ancient Roma, human begin to appreciate how amazing a marble sculptures shows!
In what ways do people utilize marble?
Marble can be found throughout the globe, is accessed typically through mining and is utilized as both a dimension stone and as a crushed aggregate material. As dimension stone, marble has been most notably used in the construction of architectural design elements.
From marble sculptures and monuments to flooring, walls, marble countertops, marble basins, marble sinks, marble fountains, marble bathtubs and even entire buildings, marble has been widely applied. Of the latter, marble is most known for its use in the creation of famous sculptures and buildings.
Some famous examples are the Statue of David (by Michelangelo), the Taj Mahal (Agra, India), the Washington Monument (Washington D.C., USA), and the Pantheon (Rome, Italy). As an aggregate material such as crushed stone chips, marble can be used as both a construction material and landscaping for foundations, rock gardens, roads and pathways due to being resistant to weathering.
Additionally, when ground into a powder, marble is used within the agricultural sector to neutralize acidic soils (when heated into calcium oxide) and incorporated into animal feed as a nutrient calcium source. Ground marble has also been used as a standard acid neutralizing agent in the chemical industry and healthcare (e.g., antacids), as well as a material whitener (e.g., paints, paper, pastes), and as a mild abrasive in cleaning products.
The word “marble” originated from the ancient Greek word “mármaros” or shining/crystalline stone, which highlights the transparent quality and low refractive index of marble.
This causes marble to faintly lustre under light sources making it appear softer, lifelike and warm (especially when sculptures are considered). In addition to the latter, other unique qualities separate marble from other comparable materials.
On the Mohs hardness scale, which measures the resistance a substance has to scratching and abrasion, marble is considered moderately hard (Mohs hardness of 3-4), moderate-fine grain size, low porosity (0.5-2%), low density (2.4-2.8 g/cm3) and a granular texture.
Freshly quarried marble is especially soft and easy to shape and as it ages marble is known to become harder and more durable. Marble is considered more durable than limestone (e.g, travertine) and sandstone although less durable than granite.
The latter characteristics combined leads marble to being one of the most (if not the most) preferred shaping surface (e.g., marble carving and marble sculpting) due to the ease in which high polish and fine details can be applied versus other materials (e.g., granite, sandstone, travertine).
White marble in particular is held in prestige by stone sculptors for having the finest and uniform grain size and notable shatter resistance. Other characteristics of marble include being heat resistant yet cool to the touch, making it ideal for use as a marble fireplace or a countertop when baking or cooking.
Marble is also effectively utilized both indoors and outdoors usage, although due to marble’s natural susceptibility to biological, chemical and mechanical weathering, consistent maintenance and the application of sealant (e.g., impregnator) will increase marble’s extensive longevity.
Another amazing marble products happens more often in streets of Europe is marble door-surround.With the beautiful color and pattern variation, a marble door surround could suit for indoor and outdoor use.
The etching and wear of marble as it ages has been found to be appealing to observers who enjoy a worn-in and inhabited look. In closing, the attractive lustre marble emits, alongside its other unique characteristics, all add to its timeless impactful presence within the design world making it a highly sought after and desirable material.
What is granite?
Granite is an igneous rock formed by the slow crystallization and cooling of magma many kilometers below the earth’s surface. The rate at which crystallization of granite occurs determines the crystal grain size of the intrusive rock (moderate to coarse granular/phaneritic texture, visible with the naked eye) which make up the granite. Two main groupings of granite exist based on grain size and they are aplite (granite composed of finer grains developed typically at shallower depths thus faster cooling) and pegamatite (granite composed of grains greater than one centimeter across typically formed at greater depths thus slower cooling).
The composition of granite consists of collectively interlocked quartz and feldspar minerals as the majority with various other accessory minerals in the minority (e.g., mica, amphiboles).
What color choices do I have If I want a sculpture, fountain , fireplace or stone tub made of granite?
Common granite coloration ranges from white, pinks, and orange (from quartz and feldspar) to grays and blacks from mica, amphibole and other minor mineral content which can form mottled, speckled and vein patterning on the rock depending on mineral composition.
Where does granite fountain/granite bathtub material come from?
Granite is the most commonly found intrusive rock on earth and can be found throughout the globe as part of the earth’s continental crust where significant weathering or other activity has removed softer upper material layers. These exposed areas of granite (e.g., mountain range cores) are known as plutons which are the easiest to access for mining and extraction purposes.
Granite mining compared to other rock materials is considered an intensive process due to the hardness and durability of granite. Leading producers of granite include India, Brazil and China although granite is also mined in Canada and the United States and elsewhere globally.
Can granite decorate everything in home and garden?
Granite is typically utilized as both dimension stone and crushed stone aggregate. As a dimension stone granite has been used to create a variety of design and architectural amenities such as granite stair treads, granite tiles, granite curbing, granite doorsurround granite counters-top, granite basins, granite veneer/backsplashes, whole buildings, curling sport stones, granite monuments and granite sculptures and the most popular item: granite bathtub ! Some famous sculptural monuments and buildings composed of granite include the Brahadeeshwara Temple (First Granite Temple, 1010AD, Tamil Nadu, India), Mount Rushmore (Massive sculpture, South Dakota, United States). As an aggregate material granite has been used as construction fill, granular roads, landscaping stone, and railroad ballast.
Why is granite such a popular material used for design and decoration purposes such as granite bathtub and granite fountain?
If you are curious,the word “granite” originated from the ancient latin word “granum” meaning “grained stone”, and the properties this stone contains has made it highly revered in the building and design industry.
Compared to the other rocks in this list, granite is considered on average the hardest (Mohs hardness of 6-7) , least porous (0.5-1.5%), most dense (2.6-2.8 g/cm3) and most weathering resistant (e.g., biological, chemical, physical weathering) rock.
This durability increases in the darker colored granites and extends its value and utility for both indoor and outdoor applications. Similar to marble, granite accepts fine polish and sculpting details although granite gives off a “colder” looking surface rather than the “warmer” luster of marble and is more difficult to carve.
What makes granite more beneficial than other materials? The answer range from easy to maintain to heat resistant!
Granite is easier to maintain and protect (e.g., sealants) than the other materials due to its lower porosity and resistance against non-pH balanced substances (e.g., liquid staining and etching) and scratch/chip resistance due to its properties.
Lastly, granite is the most heat resistant material (e.g., granite fireplaces, granite mantle, granite countertops). Although, due to the durability of granite, an increase in energy is required to form and shape it leading it to typically be more expensive to produce than some of the other rocks on this list (e.g., using diamond tipped tools, and greater wear on equipment).
Within the design and decor sector, granite is associated with prestige of its owner due to its durability and unique patterning.
To summarize, granite is one of the hardest natural stone material on earth. From granite stone planter to stone fountain /granite fountain, you could choose granite as your first choice If you want it to last forever and don't need to worry about the maintenance.
What is sandstone?
Sandstone is a sedimentary rock formed by the weathering of rocks, minerals and other material which are then transported long or short distance from its origin, deposits and accumulates within a basin or depression (terrestrial or aquatic). Once deposited, further weathering, burying, and cementing of the deposited material forms the sandstone which will then mature chemically and physically over time.
That means, If you choose a sandstone bathtub, It means this piece of sandstone has been waiting for you for tens of thousands of years under all kinds of weather. As sandstone matures, quartz content increases leading to greater chemical stability (less feldspar and other components) and grain size/shape become more uniform (smoother granular/clastic texture).
There are four main components of sandstone and they are the grains, matrix, cement and pores. The grains and the matrix, (finer grains) ranging from 0.063-2mm across, make up the supporting frame and are composed of materials deposited within the same time period.
The grains which make up the supporting frame are composed primarily of quartz, followed by feldspar (which also make up the majority of sandstone entirely), with rock fragments,mica, and heavy minerals making up the minority, whereas the matrix is composed mainly of silt and clay.
The cement and pore spaces occur post-deposition and are primarily the result of mineral precipitation and dissolution of CaCO3 (usually as calcite) and silica.
Which sandstone color can I choose for a sandstone bathtub?
Common sandstone coloration includes white, yellow, brown, pink, red, green, grey, and black depending on region acquired, and displays unique banding swirling and speckled patterns that are uniquely characteristic of sandstone. Among all these beautiful color, yellow and grey sandstone are the most popular ones and red and pink are rare and expensive.
For example, Marblebee is the only company has design a grey sandstone bathtub and make it a beautiful stone tub:
Grey sandstone bathtub looks like a concrete bathtub, but has way higher quality than a concrete bathtub. Concrete tub would vary according to different weather and humidity. It might easy crack due to dryness. On the other side of the spectrum, Sandstone bathtub has an better look and never would crack under any condition of weather in your garden or bathroom. Don't forget that this piece of grey sandstone has been waiting for your for thousands of years under all kinds of weather from mother earth.
The other beautiful yet popular color is yellow sandstone, Yellow sandstone is used in all kinds of decoration statue, like sandstone fountains, sandstone fireplaces, sandstone bathtub or planters etc.
Sandstone is the second most commonly found sedimentary rock on earth (most common rock is shale) and composes 10-20% of the earth’s crust. This rock is typically utilized as both dimension stone and crushed stone aggregate.
As a dimension stone sandstone is used to create a variety of design and architectural amenities such as sandstone sculptures, sandstone monuments, sandstone flooring, sandstone countertops, sandstone basins, curbing, grinding stones, and entire buildings.
Some famous sculptural monuments and buildings composed of sandstone include the monuments and buildings of Petra (Jordan), and the facade of the White House (United states, Washington D.C.). Sandstone aggregate is also utilized as fill, paving material, landscape stone, and in glass production (when high in quartz content).
What makes sandstone more beneficial than other materials for garden wall fountain or stone tubs?
The term sandstone originated from the combination of the words sand and stone and is applied to a variety of building and architectural applications. When compared to the other materials on this list, sandstone is considered a harder material (Mohs hardness of 6-7), with the highest porosity (5-25%), and the lowest density (2.1-2.8 g/cm3) depending on maturity.
This combination of high durability and high porosity and low density makes sandstone easier to carve and shape than marble or granite, although the same degree of fine detailing and polish cannot be achieved with sandstone.
Sandstone also lacks the low refractive index of marble, thereby appearing more opaque in comparison. Additionally, sandstone is more susceptible to acid etching and oil staining than marble due to its CaCO3 content and porosity, although with regular maintenance and the application of sealant, sandstone can be effectively preserved indoors and outdoors.
As a surface sandstone has been noted to be especially slippery when wet. As a design material, sandstone feels cool and hard to the touch yet provides a contrasting warm earth tone coloration plate and smooth patternings at a more cost effective price than marble or granite making it a popular choice for many consumers.
What is travertine? Why is travertine such a popular material used for design and decoration purposes?
Travertine is a sedimentary rock classified as a type of limestone produced through a process of chemical precipitation from freshwater or marine environments.
To be considered a chemical sedimentary limestone, a rock must be composed of at least 50% calcium carbonate (CaCO3) usually as calcite, formed when geothermally heated alkaline-saturated water containing dissolved gases and minerals are present (e.g., steam vents, waterbody mouths).
Once reaching the water surface or subsurface cavern, precipitation takes place via gas release, evaporation and surface deposition creating travertine in a variety of forms including flowstone, stalactites, stalagmites and other large masses. These processes most frequently take place in the shallower parts of the ocean between 30o North and South latitudes.
Travertine color and patterning variations are caused by chemical or mineral impurities, surface/cave environment content and organic material presence during formation. Colors include white (lack impurities), cream, tan, yellow, orange, green, brown, blue, black etc., and patterns can include layered bands with distributed surface holes of varying size.
Higher value travertine is seen to typically have smaller and fewer holes and in general, travertine has been interpreted to have an endearing “olden time” appearance.
In what ways do people utilize travertine?
Chemical limestones like travertine are less abundant than biological limestones which form through the lithification of debris rich in calcium carbonate (CaCO3) accumulated through sedimentation in aquatic environments.
Travertine is found globally with some of the main areas of occurrence including areas of Turkey, Italy, Mexico and Peru. Some famous natural deposits of travertine include Tonto Natural Bridge (Payson, Arizona, United States), Huanglong Valley (Sichuan, China) and the Mammoth Hotsprings (Wyoming, United States).
Historically and currently, travertine has been used as both a dimension stone and as an aggregate. As a dimension stone travertine is used to create a variety of design and architectural amenities such as travertine flooring, travertine paving stone, travertine basins, surfacing, backsplashes, stair treads, curbing, monuments, travertine sculptures , travertine fountains, travertine bathtubs and entire buildings.
Some famous sculptural monuments and buildings composed of travertine include the Colosseum (Rome, Italy), Hierapolis (Turkey, Pamukkale), and the Basilique du Sacre Couer (Paris, France).
As an aggregate, travertine (or limestone in general) is used in a variety of industries. Travertine is utilized in construction as fill, roofing components (e.g., granules), foundations (e.g., cement component), paving and as a spill sorbent.
In the mining and smelting industry, travertine is used as a pollutant filtering safety dust and as a flux stone which removes impurities from metals during processing. In the agricultural and chemical sectors travertine has been processed into effective acid neutralizing agents, animal feed fillers, and a filler for a variety of products such as paper, rubbers, plastics and paint.
What makes travertine more beneficial than other materials?
The term travertine originated from the term “lapis tiburtinus” or “tibur stone” from the ancient Roman town of Tibur (which is now known as Tivoli, Italy, in present time). When comparing with the other materials on this list, travertine is considered a moderately hard material (Mohs hardness of 3-4), with the second highest porosity (5-20%), and a density within the range of granite and marble (~2.7 g/cm3).
This combination of being softer than sandstone and relatively more porous than marble and granite makes travertine the easiest to shape and carve. Fine detailing in travertine is harder to produce than in marble due to travertine being less uniform in granular structure.
Limestones (e.g., travertine) also lack the low refractive index of marble, thereby appearing more opaque in comparison. Compared to marble and granite, travertine is also more susceptible to weathering (e.g., chemical, physical, biological) due to its CaCO3 content and porosity.
Similar to sandstone, with proper care and maintenance, travertine can be used effectively both indoors and outdoors. Economically travertine is less expensive than marble or granite and comparable in cost to sandstone depending on region. In closing, travertine as a design material can be effectively shaped like that of marble, while also being cost effective and able to give off an olden time charm through a variety of colors and banded patternings.
Multi stone references
Chemistry References for multiple stone specifically