How do we know its a gem from Outer Space?

A few years ago some meteorite collectors decided to facet gem-quality olivine and have them certified by GIA. GIA compared
Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources. They completed the study by using laser ablation–inductively coupled plasma–mass spectrometry (LAICP- MS).
They found that among the 32 elements analyzed, six of them—Li, V, Mn, Co, Ni, and Zn—provided an excellent separation between pallasitic and terrestrial peridot.
http://www.gia.edu/doi/10_5741-GEMS_47_3_208
http://www.gia.edu/gia-news-research-GIA-Tests-Extraterrestrial-Gemstones-Down
Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources. They completed the study by using laser ablation–inductively coupled plasma–mass spectrometry (LAICP- MS).
They found that among the 32 elements analyzed, six of them—Li, V, Mn, Co, Ni, and Zn—provided an excellent separation between pallasitic and terrestrial peridot.
http://www.gia.edu/doi/10_5741-GEMS_47_3_208
http://www.gia.edu/gia-news-research-GIA-Tests-Extraterrestrial-Gemstones-Down