IIE iron meteorite
Encyclopedia
The iron meteorite
s of the IIE chemical type are octahedrite
s of various coarseness, most of which contain numerous inclusion
s of recrystallized
stony silicate
s.
They have mineral compositions and oxygen
isotope
ratios very similar to the H chondrite
s, which makes it probable that they originate from the same parent body. The best candidate for this parent body is the S-type asteroid
6 Hebe
. Unlike most iron meteorites, the type IIE are thought to have been melted out of the chondritic surface of the parent asteroid by impacts during its early history.
It is a rare type with 21 known members as of 2009.
Iron meteorite
Iron meteorites are meteorites that consist overwhelmingly of nickel-iron alloys. The metal taken from these meteorites is known as meteoric iron and was one of the earliest sources of usable iron available to humans.-Occurrence:...
s of the IIE chemical type are octahedrite
Octahedrite
Octahedrites are a class of iron meteorites within the structural classification. They are the most common class of iron meteorites.They are composed primarily of the nickel-iron alloys: taenite - high nickel content, and kamacite - low nickel content....
s of various coarseness, most of which contain numerous inclusion
Inclusion (mineral)
In mineralogy, an inclusion is any material that is trapped inside a mineral during its formation.In gemology, an inclusion is a characteristic enclosed within a gemstone, or reaching its surface from the interior....
s of recrystallized
Recrystallization (geology)
In geology, solid-state recrystallization is a metamorphic process that occurs under situations of intense temperature and pressure where grains, atoms or molecules of a rock or mineral are packed closer together, creating a new crystal structure. The basic composition remains the same...
stony silicate
Silicate
A silicate is a compound containing a silicon bearing anion. The great majority of silicates are oxides, but hexafluorosilicate and other anions are also included. This article focuses mainly on the Si-O anions. Silicates comprise the majority of the earth's crust, as well as the other...
s.
They have mineral compositions and oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
ratios very similar to the H chondrite
H chondrite
The H type ordinary chondrites are the most common type of meteorite, accounting for approximately 40% of all those catalogued, 46% of the ordinary chondrites, and 44% of the chondrites....
s, which makes it probable that they originate from the same parent body. The best candidate for this parent body is the S-type asteroid
S-type asteroid
S-type asteroids are of a stony composition, hence the name. Approximately 17% of asteroids are of this type, making it the second most common after the C-type.-Characteristics:...
6 Hebe
6 Hebe
6 Hebe is a large main-belt asteroid, containing around half a percent of the mass of the belt. Its apparently high bulk density , however, means that by volume it does not rank among the top twenty asteroids...
. Unlike most iron meteorites, the type IIE are thought to have been melted out of the chondritic surface of the parent asteroid by impacts during its early history.
It is a rare type with 21 known members as of 2009.