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How can a meteorite be identified as coming from Mars?

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Meteorite The Hoba meteorite, lying where it was discovered in 1920 near Grootfontein, Namibia. The largest meteorite on Earth and an iron meteorite by classification, it consists of a nickel-iron alloy and is estimated to weigh about 60 tons.

Scientists identify meteorites as originating from Mars through several key lines of evidence:

Age: Many Martian meteorites are volcanic rocks with ages between 150 million and 1.3 billion years. Because these rocks are significantly younger than the 4.5-billion-year age typical of most meteorites, they must have originated from a large, geologically active body capable of sustaining volcanic activity in the relatively recent past.12
Isotopic Composition: These rocks exhibit distinct ratios of oxygen isotopes that differ from those found in Earth rocks, lunar samples, and other meteorites.1
Atmospheric Gases: The most definitive proof comes from trapped gases found within some of these meteorites. The composition and relative abundances of these gases (including noble gases, nitrogen, and carbon dioxide) are identical to the Martian atmosphere as measured by the Viking landers.12

These fragments are believed to have been ejected from the Martian surface by large impacts, eventually falling to Earth after traveling through space.12