Shell limestone properties: types, grades and use
In construction, many different materials have been used since ancient times. Some required enormous effort to extract and process, while others were simple to quarry but had unique properties and broad areas of application. Shell limestone belongs to the second group. This article discusses this material and its special useful properties.
What Is Shell Limestone?
This material has many names. Some call it shell rock, others use regional names. Regardless of the name, it is the same stone with a unique formation history. Unlike many other natural materials, shell limestone does not require a large amount of equipment for extraction and further processing. In ancient times, it was quarried by the simplest methods and used for building homes without additional processing.
Types and Grades of Shell Limestone
Like any other construction material, shell limestone has its own classification. Depending on external characteristics, it can be yellow or white. Yellow shell limestone is stronger than white. One of the main characteristics of this stone is strength. Depending on strength, it is divided into grades. Grades determine the stone’s area of application and cost.
| Grade | M10 | M20 | M25 | M35 |
|---|---|---|---|---|
| Strength | 10 kg/cm2 | 15 kg/cm2 | 25 kg/cm2 | 35 kg/cm2 |
As can be seen from the table, the number after the letter M indicates shell limestone strength. The higher the number, the stronger the stone. M10 stone is very loose and has limited use. The most popular grade is M25. Such shell limestone combines sufficient strength and good thermal insulation properties. It is important to understand that high porosity usually lowers strength but improves thermal insulation.
Unique Properties of Shell Limestone
Shell limestone is light and porous. This material consists of fossilized remains of marine organisms and is mainly represented by calcium carbonate. Thanks to its porous structure, it has good thermal insulation properties, but claims about a pronounced healing effect of such stone in a house should be treated cautiously.
The following properties of shell limestone can be noted:
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Environmental friendliness. Shell limestone owes this property to its composition. The stone consists entirely of natural components.
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As a natural limestone, shell limestone usually has a low radiation background, but for construction use this indicator should be confirmed by a certificate or laboratory control.
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Antibacterial properties, associated with the content of iodine, salts and other trace elements.
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Sound insulation and thermal insulation properties. The presence of pores gives shell limestone good sound and heat insulation indicators.
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It has filtering ability, again because of its porous structure.
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Shell limestone is completely neutral toward other construction materials.
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In summer it retains coolness, and in winter it retains heat.
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Fire resistance. Although shell limestone cannot burn, it can burn out under constant high temperatures.
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It is not subject to rotting or corrosion because it has a natural composition.
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Thanks to its strong structure, it resists abrasion processes for a long time.
Shell limestone is a natural construction material with useful properties and expressive texture. It is used in low-rise construction, finishing and decorative work. When choosing it, strength grade, porosity, moisture content and operating conditions should be considered.