Rocks are divided into three categories: igneous, sedimentary and metamorphic rocks. Onyx marble is included in the international classification. while marble is known as marble.
Marble and marble are both metamorphosed stones. While marble is subjected to more temperature and pressure than marble.
What is marmar?
Building marble, which is also known as onyx marble in the world, is a stone that is used in sculpting and interior spaces of buildings, including kitchens, bathrooms, stairs, making mosaics, building interior floors, wall decorations, etc.
The Taj Mahal, Michelangelo’s statues, and the New York Public Library are all made of marble. This stone has large and interlocked crystals that can be identified from sedimentary rocks such as marble.
How marmar is created
Marmar is a type of stone resulting from the metamorphosis of limestone or dolomite. When limestone is subjected to high pressure and heat, it recrystallizes and thus marble is formed.
Ingredients of marmar
The main mineral of marble is calcite, and the color of the stone is white with its high purity (99% calcium carbonate).
This type of stone is used in sculpture. Also, high-purity marble is transparent and allows light to pass through; For this reason, they use this property in lighting. Marble is sometimes accompanied by impurities that change its original color.
These impurities can be iron oxide, silica, mica, serpentine, and graphite, etc., which cause the formation of marble in different colors, including purple, gray, red, green, yellow, and black.
Marmar specifications
• Water absorption = less than 1%
• Specific weight = 7.2 grams per cubic centimeter
• Disruption: between 0.3 and 1.2 percent
• Resistance to humidity and weathering = low
• Resistance to scratches and wear = low
• Compressive strength = 1121 kg/cm2
• Price compared to its counterpart = high
What is marble stone?
Marble is a term that is used only in Iran, this term is equivalent to the word marble in other languages. This stone is also called Sanandji stone, but according to scientific principles and rules, there is no such thing as marble.
This stone is used in paving, floors and stairs. In fact, marble is the condensed lime that is known in the world as Compact LimeStone; But in some cases, marbles are also seen that have fossils in their texture, these types of stones are called Fossiliferous LimeStone.
How marble stone is created
Marble or dense limestone is a chemical sedimentary rock that is formed by the pressure of the upper layers and the condensation of calcium carbonate deposits and the combination with aragonite or dolomite.
This stone is often formed in warm waters, which is the result of the pressure of sediments of the upper layers on algae, corals or calcium carbonate deposits. Fossils are often seen in the layers of marble stones. During the formation of marble stone, in addition to chemical and biochemical processes, sometimes we also see a weak transformation.
Ingredients of marble
The main mineral and mother stone of marble is calcite, which is often combined with aragonite and sometimes with dolomite and has a texture similar to sugar. Calcites are actually the result of crystallization of calcium carbonate.
Pure marble is white, but its different colors are created due to the presence of various impurities such as hematite, limonite, quartz, carbon and clay compounds, and colors such as cream, red, brown, pink, black, mustard, green, etc. They create
Types of marble according to the transformation of the mother stone
Marble stones are divided into three categories based on the type of transformation of the mother stone:
• Chinese marble stone: this stone has undergone less transformation than crystal and cloudy stone. This stone has a texture consisting of small and equal-sized grain crystals. Chinese marble has three categories: white porcelain, gray porcelain and crystal porcelain.
• Crystal marble stone: This stone has undergone severe to moderate transformation compared to porcelain stone and crystal. The texture of this stone consists of large and equal-sized grain crystals.
• Cloudy marble stone: this stone has been transformed at high temperature and light and dark minerals are placed in it in the form of non-aligned bands.
Characteristics of marble stone
Here, for example, we examine the characteristics of a marble stone:
• Hardness and resistance to fire and erosion = appropriate
• Disruption=very low
• Water absorption = 0.31%
• Specific weight = 2.67 grams per cubic centimeter
• Frost test result=accepted without discoloration, cracks and fissures
• High resistance to humidity and weathering
• Compressive strength in dry state = 1020 kg/cm2
• Compressive strength in saturation = 980 kg/cm2
• The stone can be cut and regenerated
The main issue that differentiates marble and marble is the way they are formed, and this is the factor that has affected their resistance to various pressures.
In general, marble has more hardness and resistance against erosive and destructive factors. Another difference between marble and marble is their surface. Marble stone is more polished than marble, that’s why its use is more useful in stairs, floors and the exterior of the building.
But the most common use of marble is to decorate walls and make statues. Despite these differences, the main ingredient of both is lime.