Aesthetic characteristics
Technical characteristics

AESTHETIC CHARACTERISTICS

1) Colour
2) Pattern
3) Grain

1) Colour

The colour of a material is usually by far the most important element in the determination of its commercial potential. As in many others carbonatic rocks, the more or less dark pigmentation is due to carbonized organic material. The yellowish groundmass with varying shades of cream and beige is due to the presence of not carbonized organic material. Another almost constant feature of these materials is the occurrence of thin veins, varying from a yellowish colour to a reddish colour, caused by the presence of bauxite.

2) Pattern

The pattern of a rock is formed by the spatial orientation of the individual component in the rock mass. The pattern of our stone is generally Oriented, but in some cases it may be homogeneous or cloud-like (this is created artificially by cutting veined materials almost parallel to the direction of the bedding plane).

3) Grana

The grain defines the size and, in some cases, the shape of the crystalline or lithic elements which constitute a rock. In practice, in addition to its influence on the aesthetic characteristics of a material, the grain size is also important as regards the physical-mechanical properties of a material. Our stones are fine-grained.

TECHNICAL CHARACTERISTICS

1) Mineral and chemical composition
2) Origin
3) Structure
4) Texture
5) Physical properties
6) Mechanical properties

1) Mineral and chimical composition: calcareous

The rock is made almost exclusively by calcite, in a percentage varying from 96% to 98,7%.

The average percentages of the chimical elements which form the rock are:
- Calcium oxide = 53,05%
- Carbon dioxide = 43,10%
- Aluminium oxide = 0,65%
- Iron oxide = 0,25%
- Magnesium oxide = 0,25%
- Silicon dioxide = 0,10%

2) Origin: sedimentary and biochemical.

The origin of these rocks is due to the accumulation of peexisting debris and the direct chemical precipitation of the minerals of wwhich they are composed. Paleographical and mycropaleontological studies proved that the sedimentation occurred in a submarine environment, in not much deep areas.

3) Structure: microcrystalline

The microscopical crystals of calcite form the cement for the calcareous sediment and the millimetric round or subovoidal nodules.

4) Texture: dense.

These limestones are defined dense because of their texture. In soft limestones the texture is porous.

5) Physical properties:

- the unit weight per volumeIt is the ratio between the weight and the volume of the material. It provides informations as to the compactness of the material and hence to its strnght and durability. The average unit weight is of 2,40 to 2,70 gr/cmc.

Il valore medio di riferimento della loro categoria (Calcari compatti) varia tra 2,40 e 2,70 gr/cmc.

- Coefficient of compactness: It is the ratio between the unit weight per volume and the specific gravity of a rock. The lower is the number of holes inside the material, the nearest to 1 is it.

- Coefficient of porosity: It denotes the volume of the holes inside the material compared to the volume of the rock. The average coefficient is between 1 and 2%.

Il valore medio di riferimento della loro categoria (Calcari compatti) varia tra 1-2%.

- Coefficient of absorption: It defines a material's capacity to absorb liquids. It is important to know a material's absorption if the material is to be used where it is frequently in contact with liquids.The average coefficient is below 1,00%.

Il valore medio di riferimento della loro categoria (Calcari compatti) è inferiore all'1,00%.

- Coefficient of thermal expansion: It establishes a material's abilty to expand when subject to high temperatures. This is important when a material is to be used in particularly hot environments or climates. The average coefficient varies from 0,0040 to 0,0080 mm/m°C.

Il valore medio di riferimento della loro categoria (Calcari compatti) varia tra 0.0040 e 0,0080.

6) Mechanical properties:

- Compressive strenght: It defines a material's ability to withstand loads.The average value varies from 800 and 2000 kg/cmq.

Il valore medio di riferimento della loro categoria (Calcari compatti) varia tra 800 e 2000 kg/cmq.

- Compressive strenght after freeze-thaw cycles: It defines a material's ability to withstand loads in environments with significant temperature changes above and belove 0°C.

- Modulus of rupture: It establishes a material's ability to withstand bending pressure. This is extremely important for a dimension stone material since mechanical stress which causes bending occurs in many applications (rooves, shelves, lintels, floating floors, stairs, etc. ). The average value is between 80 and 200 kg/cmq.

Il valore medio di riferimento della loro categoria (Calcari compatti) varia tra 80 e 200 kg/cmq.

- Impact strenght: It gives indications as to the strenght of a material subjected to concentrated loads. This is fairly important when a material is to be used for external and internal floorings and shelves.

- Abrasion resistance: It is the ability of a rock to withstand wear. This is fundamental in assessing a material's suitability for internal and external flooring, shelves, etc.