OUT 18015

Classification: Ordinary Chondrite H6

Explainer: This means that the sample is from an asteroid parent body. It represents early Solar System material which includes chondrules (small round melt droplets). It is from a very common type of chondrule-bearing meteorite called the ordinary chondrite class. This particular type is an ‘H’ type – meaning it has high concentrations of iron (i.e. iron metal). The meteorite is also a type 6 sample – which means that it has been highly metamorphosed (heated and/or held under high pressure). You can see more about where this sample fits into the meteorite classification scheme by looking at this page.

Description: Taken from the Meteoritical Bulletin for OUT 18015

History: The meteorite was recovered as part of the Lost Meteorites of Antarctica project, which was funded in the UK by the Leverhulme Trust and supported by the British Antarctic Survey and the University of Manchester. These samples were collected as part of the project’s first field season in austral summer December 2018 – January 2019 by a two person field party consisting of Katherine Joy and Julie Baum. Found on blue ice surface (stuck on ice) at Outer Recovery Icefields ice field 3 (west icefield). Altitude 1408 m.

Physical characteristics: Mass: 850.92 g. Pieces: 1. Dimensions: 15 cm x 12 cm x 6 cm. An irregular, dark brown part stone with 40% black fusion crust.

Petrography: Equilibrated texture with some small (up to 1 mm) poorly defined chondrules. Metal and sulfide (up to 1 mm) throughout.

Mineral compositions and geochemistry: All analyses by EPMA. Olivine Fa 19.2±0.3 (N=11), Pyroxene Fs 16.9±0.4 (N=11), Wo 1.5±0.2 (N=11).

Specimens: 848.54 g type specimen (main mass) held at the NHM London.

Project comments: This was a really large sample found on a very productive day of searching. We suspect that this represents one of several similar stones found at the field site (they all look ‘chocolaty’ brown (Katie’s field notes) with a similar type of irregular dull black fusion crust), which we hope to look at in more detail through pairing relationships.

Sample images and videos:

OUT 18015 sample in the lab after defrosting. Image: Lost Meteorites of Antarctica / The University of Manchester
OUT 18015 sample in the lab after defrosting. Image: Lost Meteorites of Antarctica / The University of Manchester
OUT 18015 sample in the lab after defrosting. Image: Lost Meteorites of Antarctica / The University of Manchester
OUT 18015 sample in the field. Image: Lost Meteorites of Antarctica / The University of Manchester
3-D model of OUT 18015 meteorite produced by photogrammetry (Harvey et al., LPSC, 2020). Video: Thomas Harvey / Lost Meteorites of Antarctica / The University of Manchester