Is pyrrhotite a cleavage or fracture?

Is pyrrhotite a cleavage or fracture?

Pyrrhotite is an iron sulfide (FenSn+1) mineral with brass-yellow to copper-red color (Fig. 1.44). The crystal system is monoclinic with hexagonal polytype, and it has no cleavage. The mineral depicts uneven fracture, metallic luster, and dark green to black streak.

What is the difference between pyrite and pyrrhotite?

Pyrite is a mineral which is found in stone and produces sulfuric acid when it oxidizes upon contact with humidity and oxygen. Pyrrhotite is a mineral species composed of iron sulfide and is of a bronze yellow color, blackening when exposed to air.

What mineral group is pyrrhotite?

niccolite group
Pyrrhotite, iron sulfide mineral (Fe1–xS) in the niccolite group; in it, the ratio of iron to sulfur atoms is variable but is usually slightly less than one.

What is the hardness of pyrrhotite?

Pyrrhotite (Fe1-xS, where x = 0 – 0.2) is a common sulfide mineral exhibiting a brownish-bronze color with a metallic luster. Physical properties include a hardness of 4 on the Mohs scale, a specific gravity ranging between 4.58 and 4.65 and is magnetic, but with varying intensity depending upon the iron content.

What is pyrrhotite damage?

Pyrrhotite is a mineral that expands when exposed to water and oxygen. If pyrrhotite is present in concrete—as it is in the foundations of at least 1,600 Connecticut and Massachusetts homes—the concrete can crack and crumble. It can cost $150,000 to raise a house and remove and replace the foundation.

Is pyrrhotite in all concrete?

Is pyrrhotite found in every concrete foundation? No. We have tested many homes that are pyrrhotite free. The presence (or absence) of pyrrhotite depends on the rock aggregate in the concrete and where it was derived from geologically.

What does a pyrrhotite rock look like?

Pyrrhotite is an iron sulfide mineral with the formula Fe(1-x)S (x = 0 to 0.2). It is a nonstoichiometric variant of FeS, the mineral known as troilite….

Pyrrhotite
Color Bronze, dark brown
Crystal habit Tabular or prismatic in hexagonal prisms; massive to granular
Cleavage Absent
Fracture Uneven

What does pyrrhotite look like?

Pyrrhotite is also called magnetic pyrite, because the color is similar to pyrite and it is weakly magnetic. The magnetism decreases as the iron content increases, and troilite is non-magnetic….

Pyrrhotite
Mohs scale hardness 3.5 – 4.5
Luster Metallic
Streak Dark grey – black
Specific gravity 4.58 – 4.65, average = 4.61

Is pyrrhotite a cleavage or fracture? Pyrrhotite is an iron sulfide (FenSn+1) mineral with brass-yellow to copper-red color (Fig. 1.44). The crystal system is monoclinic with hexagonal polytype, and it has no cleavage. The mineral depicts uneven fracture, metallic luster, and dark green to black streak. What is the difference between pyrite and pyrrhotite? Pyrite…