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The world's meteorite collections contain a very rich picture of what the early Solar System would have been made of, however the lack of spatial context with respect to their parent population for these samples is an issue. The asteroid population is equally as rich in surface mineralogies, and mapping

the northern Hemisphere dominates our knowledge of Mesozoic and cenozoic fossilized tree resin (amber) with few findings from the high southern paleolatitudes of Southern Pangea and Southern Gondwana. Here we report new Pangean and Gondwana amber occurrences dating from ~230 to 40 Ma from Australia (Late triassic and paleogene of tasmania; Late cretaceous Gippsland Basin in Victoria; Paleocene and late middle Eocene of Victoria) and New Zealand (Late Cretaceous Chatham Islands). The Paleogene, richly fossiliferous deposits contain significant and diverse inclusions of arthropods, plants and fungi. These austral discoveries open six new windows to different but crucial intervals of the Mesozoic and early cenozoic, providing the earliest occurrence(s) of some taxa in the modern fauna and flora giving new insights into the ecology and evolution of polar and subpolar terrestrial ecosystems. Amber, or ancient tree resin, is valued most highly in science as an exceptional preservation medium for small organisms as fossil bioinclusions. In paleontology, diverse animals, plants and microorganisms have the potential of being preserved in three dimensions in the finest of detail. Worldwide, ambers have been recorded dominantly in upper Mesozoic to lower Cenozoic rocks from Northern Hemisphere and Northern Gondwana localities, but only one southern high latitude occurrence of microorganisms and microbe-like inclusions in amber has been published from the early Late Cretaceous (Turonian) in the Flaxman and Waarre formations of southern Victoria, Australia 1. Other Late Cretaceous ambers have recently been reported from the Chatham Islands, New Zealand 2 , representing internal plant resin canals (no exuded amber), and small to minute amber fragments have been reported from the early Paleogene (early Eocene) of western Tasmania 3 , mid-Paleogene of Victoria 4 and strandline deposits of the southern coast of Australia from Victoria to the west coast 5 (Fig. 1). However, no preserved animals or plants have yet been found. Neogene ambers have been reported from the Mio-Pliocene Australian Latrobe Valley Coal, cropping out near Yallourn, Allendale and also Lal Lal in Victoria in Australia 6,7 (Fig. 1). Earlier reports of Cretaceous amber sourced from the Wonthaggi Coal Mine 7 have proved to be anomalous and not from the Mesozoic or early Cenozoic 1. Amber from Cape York, far northern Queensland, Australia, is under study to establish if it is autochthonous or allochthonous (see discussion in Supplementary Text). New

Ureilite meteorites are arguably our only large suite of samples from the mantle of a dwarf planet and typically contain greater abundances of diamond than any known rock. Some also contain lonsdaleite, which may be harder than diamond. Here, we use electron microscopy to map the relative distribution of coexisting lonsdaleite, diamond, and graphite in ureilites. These maps show that lonsdaleite tends to occur as polycrystalline grains, sometimes with distinctive fold morphologies, partially replaced by diamond + graphite in rims and cross-cutting veins. These observations provide strong evidence for how the carbon phases formed in ureilites, which, despite much conjecture and seemingly conflicting observations, has not been resolved. We suggest that lonsdaleite formed by pseudomorphic replacement of primary graphite shapes, facilitated by a supercritical C-H-O-S fluid during rapid decompression and cooling. Diamond + graphite formed after lonsdaleite via ongoing reaction with C-H-O-S gas. This graphite > lonsdaleite > diamond + graphite formation process is akin to industrial chemical vapor deposition but operates at higher pressure (∼1–100 bar) and provides a pathway toward manufacture of shaped lonsdaleite for industrial application. It also provides a unique model for ureilites that can reconcile all conflicting observations relating to diamond formation.