Effective CO 2 -storage in the shallow solid Earth mainly occurs by the formation of carbonates. Although the possibility of transport and storage of carbonates to great depth is demonstrated experimentally, ultra-deep mantle carbonates have not been found before. Applying several in situ analytical techniques on inclusions in diamonds from Juina (Brazil) originating from the lower part of the transition zone (N 580 km) or even the lower mantle (N 670 km), reveal the existence of deep Earth carbonates. These finding unquestionably show that at least locally carbonates exist within the deep Earth and may indicate that the Earth's global CO 2 -cycle has an ultra-deep extension.

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Volcanism is a substantial process during crustal growth on planetary bodies and well documented to have occurred in the early Solar System from the recognition of numerous basaltic meteorites. Considering the ureilite parent body (UPB), the compositions of magmas that formed a potential UPB crust and were complementary to the ultramafic ureilite mantle rocks are poorly constrained. Among the Almahata Sitta meteorites, a unique trachyandesite lava (with an oxygen isotope composition identical to that of common ureilites) documents the presence of volatile-and SiO 2 -rich magmas on the UPB. The magma was extracted at low degrees of disequilibrium partial melting of the UPB mantle. This trachyandesite extends the range of known ancient volcanic, crust-forming rocks and documents that volcanic rocks, similar in composition to trachyandesites on Earth, also formed on small planetary bodies ∼4.56 billion years ago. It also extends the volcanic activity on the UPB by ∼1 million years (Ma) and thus constrains the time of disruption of the body to later than 6.5 Ma after the formation of Ca-Al-rich inclusions.A large number of planetary embryos, tens to hundreds of kilometers in size, accreted within the early Solar System. In some of these embryos, internal heating triggered melting and differentiation, giving rise to a varied suite of lithologies as documented by the achondritic meteorites. Planetary crustal growth occurs via both volcanic eruptions and plutonic intrusions. Constraining these processes and the diversity of crustal materials that formed the outermost solid shell of planetary bodies is crucial for understanding Solar System planetary processes and evolution.Ureilites are among the most common achondrites and represent remnants of the mantle from a planetary body from which magmas have been extensively extracted (1−4). Several details of ureilite petrogenesis (e.g., the mode of melt extraction) remain controversial (e.g., refs. 1 and 2) because crustal rocks from the ureilite parent body (UPB) have not yet been discovered. Although tiny remnants of feldspathic and felsic melts from ureilitic breccias have been interpreted as UPB basalts or products of partial melting of plagioclase-bearing cumulates (e.g., refs. 5 and 6), it is generally assumed that the complementary melts were lost to space during explosive eruptions (e.g., refs. 7-9).A unique opportunity to gain new insights into ureilite petrogenesis was provided by the polymict asteroid 2008 TC 3 that impacted our planet October 7, 2008, in the Nubian Desert, Sudan, containing various ureilitic and ureilite-related fragments (10, 11). Among its remnant fragments collected in the strewn field, collectively named the "Almahata Sitta" meteorites, the sample ALM-A (Almahata Sitta trachyandesitic meteorite) was recovered (12). ALM-A weights 24.2 g and is covered with a greenish and shiny fusion crust (Fig. 1).The ALM-A sample described here is the only SiO 2 -rich, rapidly cooled volcanic rock among the meteorites in our collections. This rock is textura...

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