# H chondrite

- Page: https://taslar.bumba.tr/en/stones/h-chondrite/
- Turkish: H kondrit
- Also known as: Bronzite chondrite (obsolete), Olivine bronzite chondrite (obsolete)
- Kind: Meteorite
- Classification: Meteorites and impact stones › Stony meteorites
- Hardness (Mohs): 5–7
- Specific gravity: 3.22–3.58 g/cm³
- Lustre: Dull
- Transparency: Opaque
- Colours: black (fusion crust), grey (interior), with shiny metal specks
- Composition: Total iron is 25–31% by weight, over half of it metallic. The main minerals are bronzite (an orthopyroxene) and olivine (16–20 mol% fayalite), with 15–19% nickel–iron metal and about 5% troilite.
- Texture: A stony meteorite with chondrules. Most were markedly heated on their parent body: over 40% are petrologic type 5, most of the rest types 4 and 6; only about 2.5% are the little-altered type 3.
- Value ladder: 5/9 step, Ornamental stone

The commonest meteorite group: iron-rich ordinary chondrites that look like stone but strongly attract a magnet because of their metal grains.

H chondrites are the most common meteorite group, making up about 40% of all catalogued meteorites and 46% of ordinary chondrites. The “H” stands for “high”, as they hold more iron than other ordinary chondrites. Although they look stony, more than half of their iron is metallic, so they strongly attract a magnet. Their probable parent body is the asteroid 6 Hebe.

## How does it form?

H chondrites come from an asteroid that formed at the start of the Solar System from dust and chondrules but never fully melted. Material in this asteroid was heated to different degrees at different depths, so most H chondrites are petrologic types 4, 5 and 6, markedly heated and recrystallised. Only about 2.5% are the little-altered type 3.

This parent body is thought to be the asteroid 6 Hebe. As smaller asteroids that broke off Hebe in the past are themselves shattered by collisions, their fragments reach Earth.

## What is it used for?

- **Inside asteroids:** The petrologic types help show how temperature changed with depth inside the parent asteroid.
- **Meteorite–asteroid links:** Spectral comparisons with Hebe and similarities with IIE iron meteorites help study how asteroid families are related.
- **Collections and teaching:** As the commonest meteorite group, they are among the meteorites most often seen in museums and school collections.

## Famous H chondrites

Weston (H4, 1807, Connecticut), Sylacauga (H4, 1954, Alabama), Gao-Guenie (H5, 1960, Burkina Faso) and Peekskill (H6, 1992, New York) are the best-known examples.

## How to recognise it

- A black fusion crust outside; inside grey, with shiny metal specks.
- It strongly attracts a magnet and is clearly heavier than an ordinary stone of the same size.
- Chondrules can be seen on a cut face, but in most specimens they are partly blurred by heating.

## What determines its value?

Being the commonest meteorites, H chondrites are the most readily found among meteorites. A piece's value depends on its mass, the freshness of its fusion crust, how rusted it is and above all whether it belongs to a famous observed fall.

This information is educational, not buying, selling or investment advice. Value varies enormously with quality and treatment.

## Myths and misconceptions

- Myth: A meteorite that looks like stone won't attract a magnet; if it does, it must be an iron meteorite. Fact: H chondrites look stony, but with 15–19% nickel–iron metal by weight they strongly attract a magnet. Attracting a magnet alone does not show that a stone is an iron meteorite, or even a meteorite at all.

## Curious questions

**Where do H chondrites come from?**

The most likely parent body is the S-type asteroid 6 Hebe, with 3 Juno and 7 Iris as less likely candidates. The meteorites are thought to come not directly from Hebe but from impacts on small near-Earth asteroids that broke off it in the past.

## Did you know?

- They used to be called “bronzite chondrites” or “olivine bronzite chondrites” after their dominant minerals; these names are now obsolete.
- H chondrites have trace-element abundances and oxygen isotope ratios very like the IIE iron meteorites, so the two probably come from the same parent body.
- The Weston meteorite, which fell on Connecticut in 1807, is an H4 chondrite; the fall was widely witnessed and reported in the newspapers of the day.

## Where is it found?

- Weston (now Easton), Connecticut, USA (Historic source): An H4 chondrite that fell on the morning of 14 December 1807; widely witnessed, with three loud explosions and fragments falling in at least six places.
- Oak Grove, near Sylacauga, Alabama, USA (Known locality): The H4 chondrite that came through a roof in 1954 and struck Ann Hodges.
- Peekskill, New York, USA (Known locality): An H6 chondrite documented by 16 video recordings in 1992 that struck a parked car.
- Gao and Guenie, Burkina Faso (Known locality): An H5 chondrite that fell in 1960; one of the largest meteorite showers observed in Africa.

## Sources

- [H chondrite](https://en.wikipedia.org/wiki/H_chondrite), Wikipedia
- [Weston meteorite](https://en.wikipedia.org/wiki/Weston_meteorite), Wikipedia
- [Peekskill meteorite](https://en.wikipedia.org/wiki/Peekskill_meteorite), Wikipedia
- [Gao–Guenie meteorite](https://en.wikipedia.org/wiki/Gao%E2%80%93Guenie_meteorite), Wikipedia
- [Sylacauga (meteorite)](https://en.wikipedia.org/wiki/Sylacauga_(meteorite)), Wikipedia
- [Meteorite porosities and densities: a review of trends in the data (D. T. Britt & G. J. Consolmagno), Lunar and Planetary Science XXXV, abstract 2108](https://www.lpi.usra.edu/meetings/lpsc2004/pdf/2108.pdf), Lunar and Planetary Institute, 2004
- [Handbook of Mineralogy: Enstatite](https://www.handbookofmineralogy.org/pdfs/enstatite.pdf), Mineralogical Society of America


Source: https://taslar.bumba.tr/en/stones/h-chondrite/ · Licence: CC BY-SA 4.0