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The (plagioclase) lherzolitic shergottite Northwest Africa (NWA) 7397 consists of poikilitic and non‐poikilitic lithologies. Coarse‐grained low‐Ca pyroxene oikocrysts enclose olivine and chromite grains in the poikilitic lithology. The major constituents of the non‐poikilitic lithology are olivine, Ca‐pyroxene, and plagioclase. Minor amounts of chromite, ilmenite, alkali feldspar, Ca‐phosphate, and iron‐sulfide are included in the non‐poikilitic lithology. Most plagioclase grains in the non‐poikilitic lithology have become maskelynite. A melt pocket occurs in the non‐poikilitic lithology. Plagioclase in contact with the melt pocket has dissociated into zagamiite + stishovite. Apatite and merrillite entrained in the melt pocket have transformed into tuite. Olivine in contact with the melt pocket has dissociated into bridgmanite (almost vitrified) + ferroan‐periclase. Alteration products, iron oxides and hydroxides, also occur in the dissociated olivine although it is not clear when the aqueous alteration occurred. The dissociation reactions of olivine and plagioclase into the high‐pressure polymorphs (bridgmanite, ferroan‐periclase, zagamiite, and stishovite) are found from lherzolitic shergottites for the first time. The estimated peak shock‐pressure and ‐temperature conditions recorded in melt pockets of NWA 7397 are ˜23 GPa and 2,000 °C at least, respectively, based on the high‐pressure mineral assemblages. [ABSTRACT FROM AUTHOR]

High‐pressure minerals in the eucrite Padvarninkai were investigated. Parts of anorthitic plagioclase and tridymite in the host rock of Padvarninkai vitrified, indicating that the shock pressure was 22–27 GPa. Tissintite, coesite, and a majorite‐bearing garnet occurred in the shock‐melt veins of Padvarninkai as high‐pressure minerals. Tissintite, kyanite, corundum, and dense plagioclase have occurred in the anorthitic plagioclase grains. The anorthitic plagioclase was melted and tissintite crystallized from the melt after the crystallization of kyanite and corundum. The residual melt became dense plagioclase by quenching. Tridymite has also melted and coesite crystallized from the melt. The formation of tissintite and coesite indicates that the shock pressure recorded in the veins was 2–13 GPa. The temperature increased drastically in the veins (>˜3000 K) compared with the host rock (<˜800 K). Parts of the tissintite and coesite became, respectively, amorphous (or anorthite) and quartz. Two different impact events may be recorded in Padvarninkai: The first impact event brecciated a part of the host rock, and the second impact event induced the melting of the brecciated portion, resulting in the formation of shock‐melt veins where the conditions are a high temperature and a relatively low pressure. In the veins, tissintite and coesite formed first, and parts of them underwent a back‐transformation due to a long cooling time. [ABSTRACT FROM AUTHOR]