Howardites
Topic

#Stony-iron meteorites

Meteorites made of roughly equal parts metal and rock: pallasites and mesosiderites.

Lessons (3)

Courses (4)

  • How meteorites are classifiedTens of thousands of meteorites are sorted into a system of classes and groups. This lesson explains the main branches and what the labels o
  • Worlds that meltedSome early asteroids melted and separated into core, mantle and crust, then were shattered.
  • Three kinds of meteoriteScientists sort meteorites into three main kinds by what they are made of: stone, iron, or a mixture of both.
  • Inside a planet: cores, mantles and crustsNobody can drill to Earth's core, but meteorites let us hold pieces of the cores, mantles and crusts of other worlds.

Books (1)

Famous meteorites (7)

  • BrenhamA Kansas farmer's wife collected heavy black rocks for years – and proved scientists wrong about where they came from.
  • EsquelA Patagonian pallasite whose glowing golden-green crystals have made it one of the most beautiful meteorites ever found.
  • EsthervilleIn 1879 a meteorite half metal and half stone crashed onto the Iowa prairie – a rare mesosiderite, still a puzzle to scientists.
  • FukangA tonne-sized pallasite from the mountains of north-west China, packed with gem-like crystals.
  • ImilacA pallasite scattered across the Atacama Desert, whose weathered pieces look like metal sponges.
  • SeymchanFound in a stream in Russia's Far East in 1967 and thought to be an ordinary iron – until pieces with gem-like crystals turned up decade
  • Vaca MuertaA mesosiderite scattered across the Atacama Desert, named after a 'dead cow' and found by prospectors in the 19th century.

Meteorite types (10)

  • CB chondrites (bencubbinites)More than half metal, with chondrules made in a planet-sized collision. CB chondrites, named after Bencubbin in Australia, are more than 50%
  • Eagle Station pallasitesA tiny grouplet of pallasites with iron-rich olivine and nickel-rich metal, from a separate parent body.
  • HED meteorites: pieces of VestaThe howardites, eucrites and diogenites: crust and mantle rocks from the giant asteroid 4 Vesta. The meteorites this site is named after.
  • IIF ironsA small group of magmatic irons. IIF is a small magmatic group of irons with distinctive trace-element patterns. Only a handful are known.
  • IIIAB ironsThe most common iron meteorites: medium octahedrites from one asteroid core. IIIAB is the largest group of irons, about a third of all irons
  • Main-group pallasitesNine in ten pallasites: magnesium-rich olivine in metal related to the IIIAB irons.
  • MesosideritesJumbled breccias of metal and basalt, made in a violent collision. Mesosiderites are breccias of roughly equal parts iron-nickel metal and s
  • PallasitesGem-like olivine crystals set in iron-nickel metal. Pallasites contain large olive-green crystals of olivine embedded in iron-nickel metal.
  • Pyroxene and ungrouped pallasitesPallasites that fit neither main group nor Eagle Station, among them the pyroxene-bearing pair Vermillion and Yamato 8451.
  • Stony-iron meteoritesRoughly equal parts metal and silicate. Rare, and among the most beautiful meteorites.

Meteorite minerals (4)

  • BarringeriteA phosphorus-rich iron–nickel phosphide first found in a pallasite. Barringerite contains more phosphorus than schreibersite, with two metal
  • FarringtoniteA magnesium phosphate found in pallasites, formed where phosphorus from metal met olivine. Farringtonite is a simple phosphate of magnesium.
  • OlivineThe green magnesium–iron silicate that is the most common mineral in stony meteorites and the gem crystals of pallasites.
  • StanfielditeA calcium–magnesium phosphate found in pallasites and mesosiderites. Stanfieldite is a phosphate of calcium, magnesium and iron.

Glossary (12)

Questions and answers (9)

Impact craters (2)

  • DalgarangaDalgaranga is a small meteorite crater about 24 m across and 3 m deep in the Murchison region of Western Australia.
  • HavilandThe Haviland crater, in Kiowa County, Kansas, in the United States, is one of the smallest known meteorite craters on Earth, only about 15 m

Asteroids (1)

  • PsychePsyche stands out among the large asteroids because it appears to be rich in metal.

Myths and folklore (1)

People (3)

  • Eliza KimberlyThe Kansas farmer's wife who gathered heavy black stones from her family's fields and proved that they were pallasite meteorites.
  • Peter Simon PallasThe naturalist who brought a giant mass of iron and olivine from Siberia to St Petersburg, the first pallasite known to science.
  • Steve ArnoldThe American meteorite hunter who dug up a 650-kilogram pallasite at Brenham, Kansas, in 2005.

Britain and Ireland (1)

  • The Hambleton meteoriteBritain's only pallasite: olivine crystals set in metal, first mistaken for industrial slag on a moorland track.

Museums and collections (5)

Strewn fields (1)

  • The Brenham strewn fieldA prehistoric pallasite shower on Kansas farmland, with one of the smallest impact craters known. Masses are scattered over the farmland aro

Meteorites (the 60 largest of 281)