Basaltina

Description

Basalt is an igneous volcanic rock of the basic composition of the normal alkalinity series from the basalt family. The name may be derived from the Greek. βασικός - "main", or, according to another version, from the Ethiopian basal (bselt, bsalt) - "boiling", "iron-containing stone", since in the manuscripts of Pliny the Elder it is mentioned that the first basalts appeared from Ethiopia. The plutonic analogue of basalts is gabbro, and the hypabyssal analogue is dolerites. Basalt varieties include traps. Dominated among other kainotypic (slightly altered) volcanic rocks.

Basalts are usually dark gray, black or greenish-black rocks with a glassy fibrous, cryptocrystalline aphyric or porphyry structure. In the porphyry varieties, against the background of the total cryptocrystalline mass, small phenocrysts of greenish-yellow isometric crystals of olivine, light plagioclase, or black pyroxene prisms are clearly visible. The size of phenocrysts can reach several centimeters in length and make up to 20-25% of the mass of the rock.

The texture of basalts can be dense, massive, porous, amygdaloid. Tonsils are usually filled with plagioclase, basaltic hornblende, feldspar, calcite, chlorite and other secondary minerals - such basalts are called mandelsteins.

Density (2.60-3.10 g / cm3).

Basalt is used as a raw material for crushed stone, for the production of basalt fiber (for the production of heat and sound insulation materials, composite basalt reinforcement, etc.), stone casting and acid-resistant powder, paving slabs, paving stones, facing slabs, and also as a filler for concrete. Basalt is highly resistant to weathering and therefore is often used for exterior decoration of buildings and for the manufacture of sculptures installed in the open air and as a building and cladding material. The market for the production of continuous basalt fiber reinforcement is also beginning to develop.

PHYSIOCHEMICAL PROPERTIES

Volume weight:	3100 kg / m3
Compressive strength:	min 300-450 MPa
Flexural strength:	min 45 MPa
Moisture absorption:	1%
Frost resistance:	at least 50 cycles