Sericho Pallasite Meteorite Part Slice, 92.48g, Etched and Stabilized

Professionally conserved pallasite from Kenya's Habaswein find

This 92.48g part slice exposes the internal architecture of the Sericho pallasite through controlled etching that reveals both the iron-nickel matrix structure and the boundaries between metal and olivine crystal phases. The specimen has been stabilized using museum-standard conservation methods: Paraloid B-72 applied to cut edges and microcrystalline wax on polished faces. This treatment preserves the meteorite's structural integrity without adding epoxy weight, ensuring the listed 92.48g represents actual meteorite mass. The part slice format displays a cross-section through the stony-iron structure, showing how olivine crystals are distributed within the metallic host.

The etching process employed nitric acid to preferentially dissolve kamacite and taenite at different rates, creating visible topographic relief that maps the metal's crystallographic orientation. Olivine crystals appear as recessed or protruding features depending on their hardness relative to the surrounding metal. The stabilization prevents oxidation and maintains the contrast between etched metal surfaces and silicate phases, critical for long-term display and study.

Structure and features

The etched surface displays the iron-nickel matrix with visible kamacite-taenite boundaries that formed during slow cooling in the asteroid's interior. Olivine crystals appear as distinct phases embedded within the metallic framework, their margins defined by the differential etching response between silicate and metal. The part slice geometry cuts through multiple olivine grains at varying angles, creating a three-dimensional view of how these gem-quality crystals occupied space within the parent body's core-mantle boundary region.

Kamacite lamellae width and orientation vary across the specimen, reflecting the nickel concentration gradients that developed during the asteroid's thermal history. Some olivine crystals show fracture patterns consistent with impact shock, while others remain intact with sharp crystal faces preserved at the metal-silicate interface. The stabilization treatment has locked these features in place, preventing the oxidation that typically degrades iron meteorites in terrestrial environments.

Scientific context

Pallasites formed at the boundary between a differentiated asteroid's metallic core and olivine-rich mantle, likely through impact disruption that mixed these layers during the solar system's first few million years. The Sericho fall represents one of the most significant pallasite recoveries, with material showing exceptional preservation of both metal and silicate phases. Olivine crystals in pallasites provide direct samples of mantle material from asteroids that underwent the same planetary differentiation processes that created Earth's internal structure.

The iron-nickel host crystallized from molten metal at temperatures above 1400°C, then cooled at rates between 1 and 10 degrees Celsius per million years. This extended cooling period allowed nickel atoms to diffuse through the crystal lattice, creating the kamacite-taenite intergrowths visible after etching. Pallasites account for less than 1% of all classified meteorites, making them among the rarest samples available from asteroid interiors. For comprehensive background on meteorite formation and classification, see our Learn About Meteorites guide.

Frequently asked questions

Is this meteorite authenticated? Sericho is classified as a pallasite in the Meteoritical Bulletin. You can verify the classification at this MetBull search link. Each specimen includes a certificate of authenticity documenting its provenance from the 2016 Habaswein, Kenya find.

What does "stabilized" mean for this specimen? Stabilization refers to museum-standard conservation treatment using Paraloid B-72 acrylic resin on cut edges and microcrystalline wax on polished surfaces. This prevents oxidation without adding significant weight. Unlike specimens coated in thick epoxy, this piece's 92.48g weight represents actual meteorite mass, not resin filler.

What is included with this specimen? The specimen weighs 92.48g and includes a certificate of authenticity. No display stand is included unless specifically noted in the variant details.

Why do pallasites show such distinct crystal and metal separation? The olivine crystals and iron-nickel metal represent two immiscible materials that could not mix when molten. They originated at the boundary where the asteroid's liquid metal core contacted its solid olivine mantle, either through impact disruption or density-driven flow processes.

How should I store this etched and stabilized piece? The conservation treatment provides long-term protection, but store the specimen in low-humidity conditions away from direct moisture exposure. The stabilization prevents oxidation under normal display conditions, though extreme humidity or liquid water contact should be avoided.

Collector significance

Pallasites represent the rarest structural class among meteorites, and Sericho material combines scientific importance with exceptional visual clarity. The 2016 discovery provided the first significant pallasite material in over a decade, and specimens with professional stabilization treatment offer preservation quality typically reserved for institutional collections. This 92.48g part slice provides substantial size for display while maintaining the internal structure visibility that makes pallasites valuable for both collectors and researchers.

The etched and stabilized preparation demonstrates proper conservation methodology, distinguishing this specimen from untreated pieces that deteriorate over time or epoxy-coated examples that obscure actual meteorite content. Collectors seeking stony-iron meteorites value Sericho for its combination of structural clarity, gem-quality olivine, and reliable provenance from a documented find. Browse our complete Stony-Iron Meteorites collection to compare this specimen with other core-mantle boundary samples.

Meteoritical Bulletin entry: Sericho | Classification: Pallasite | Find, Habaswein, Kenya, 2016