Sericho Pallasite Meteorite – Kenya

Sericho is a well-known meteorite that was discovered in the desert of northern Kenya in 2016, and to date more than 2,800 kg have been found. It was initially thought to be several separate pieces that were later identified as part of a single meteorite. Pieces ranging in mass from <1 to 500 kg have been found in an area over 45 km long, starting a few km west of Habaswein and south of Sericha. Most of the pieces weigh over 50 kg. Meteorites found at the surface show minimal weathering. This means that their surface structure and chemical composition remain relatively unaffected by the Earth's atmospheric and surface conditions.

This meteorite is classified as a Pallasite, a group of stony-iron meteorites, and is known for its unique shape and structure.

Structure

1. Metallic part:
• Iron and nickel: Pallasites, including Sericho, are composed of alloys of iron and nickel, which gives the meteorite its metallic luster.
• Widmanstätten structures: although Widmanstätten structures are characteristic of iron meteorites, they may be present in pallasites like Sericho, but are not as prominent due to the presence of olivine crystals.
2. Olivine crystals:
• Size and shape: olivine crystals in the Sericho meteorite can range in size from small grains to large, visible crystals. These crystals are often transparent to translucent and can vary in colour from green to yellow to orange.
• Distribution: olivine crystals are embedded in the metal and are evenly dispersed throughout the meteorite. This combination of metal and olivine gives the Sericho meteorite its distinctive appearance.