This <a href="https://fineart.ha.com/itm/meteorites/martian/a-huge-slice-of-a-martian-meteorite/a/6061-49033.s" rel="noreferrer nofollow">slice</a> was made by others, but it best reveals what lies within my <a href="https://www.flickr.com/photos/jurvetson/24652029823/in/photostream/">2kg Martian</a> stone.

My focus is on the vesicles that riddle the darker shock-melt areas. These are trapped pockets of Martan atmosphere, preserved for 175 million years, and brought to Earth by meteorite strike — a sample return for free! This time capsule contains air that has been shown in analysis of similar meteorites to match the noble gas isotope signature measured by the Viking landers in 1976. The early Martian atmosphere was much thicker, warmer and wetter than it is today, possibly even capable of sustaining life.

From meteorite hunter Michael Farmer: "Not many Martian’s have any measurable atmosphere. Not enough vesicles in most."

In this <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/maps.12100" rel="noreferrer nofollow">study of trapped Martian gasses</a>, DaG 1037 provided the most data for their models:

“DaG 1037 shows the most complex distribution of shock‐melt pockets and veins, and consequently the most complex cooling history. This meteorite sample contains abundant pockets that vary in size and spatial distribution, in addition to a 1 mm wide vein cutting across the entire sample.”

As for how the gas gets there: “Shock recovery experiments have demonstrated that hypervelocity impact provides a viable mechanism for implanting a sample of ambient gases in melts produced during shock, without elemental or isotopic fractionation. This results from diffusion in a high‐pressure environment. The high‐pressure gas would diffuse into the locally molten regions of the meteorite (shock melts).

These studies show that Martian atmosphere, traced using 40Ar/36Ar as an isotopic fingerprint (as measured by Viking landers), is specifically sited within the shock melts.