Specific and volumetric weight of different types of clay
Clay is used quite widely in construction. It is a soft, plastic and fine-grained rock used for mortars, stove masonry, brick production, ceramics and other materials. Clay occurs in many soil types and acts as a binding component for fine and coarse mineral particles.
When clay is used in construction and production work, its weight often needs to be known. The mass of the material depends on clay type, moisture, density, mineral composition and impurities.
The specific weight of clay is usually understood as the ratio of material mass to occupied volume. This value varies noticeably depending on the clay type and composition. Common types of clay include:
- Refractory clay is a dense mass of blue, yellow, white or grayish color. It contains a significant amount of alumina and silica, is used for refractory products and usually has a high specific weight.
- Fuller's clay is a material containing magnesian compounds and capable of absorbing fats and oils. It often has a gray-green or olive shade and an average specific weight.
- Common, or potter's, clay is a dry and hard mass that becomes viscous and dough-like when moistened. It may have a high specific weight.
- Saline clay is a clay mass with salts and gypsum impurities. It usually has an average specific weight.
- Alum clay is a dark material that can change properties during weathering. It has average specific weight values.
- Resinous clay is a brown, yellow or dark-brown material containing iron compounds and other impurities. It belongs to denser clay types.
- Lime-containing clay has average specific weight values that depend on the share of lime inclusions.
Table of the weight of 1 m³ of clay depending on type
To estimate the weight of 1 m³ of clay, in most cases it is enough to know the material type. The table below gives the specific weight of clay and the approximate number of kilograms in one cubic meter.
| Clay type | Specific weight, g/cm³ | Weight of 1 m³, kg |
| Refractory clay | 2.44 | 2440 |
| Fuller's clay | 1.8 - 1.9 | 1880 - 1900 |
| Common (potter's) clay | 2.56 - 2.65 | 2560 - 2650 |
| Saline clay | 1.8 - 1.9 | 1880 - 1900 |
| Alum clay | 1.8 - 1.9 | 1880 - 1900 |
| Resinous clay | 2.54 - 2.57 | 2540 - 2570 |
| Ferruginous clay | 1.8 - 1.9 | 1880 - 1900 |
| Lime-containing clay | 1.8 - 1.9 | 1880 - 1900 |
Frequently Asked Questions
Can the density of clay be used for precise calculations?
The density and weight values for clay in this article are reference values. They are suitable for preliminary estimates, but design, construction, production and other critical calculations should be checked against standards, material datasheets or measurement results.
Why can the actual weight of clay differ from the table?
The actual weight of clay depends on composition, moisture, temperature, porosity, fraction size, material grade and measurement conditions. Because of this, real values may differ from the average table data.
How do you calculate the mass of clay from density?
For an approximate calculation, use the formula: mass = density × volume. If the density of clay is given in kg/m³ and the volume is in m³, the result will be in kilograms.