Stone meteorite, chondrite ungrouped - CH-UNGR, subtype 3.05, Western Sahara
NWA 5717 provides a rare peek at the raw ingredients of solid planetary bodies, and this explains the article on NWA 5717 in a Journal of the Lunar and Planetary Conference entitled"The Extra-Ordinary Chondrite: NWA 5717."
Most meteorites are ordinary chondrites (stone meteorites with silica-rich spherular inclusions called chondrules — droplets which condensed out of the gaseous solar nebula which stuck together and formed the solid planets. The vast majority of all chondrites experienced some degree of metamorphoses — their texture (and at times mineralogy) modified as a result of exposure to heat and pressure. This is not the case with NWA 5717 — the 5717th meteorite to be classified after being found in the North West African (NWA) sector of the Sahara Desert. Unlike nearly all meteorites,NWA 5717 is nearly unchanged since the time of its formation.
In addition, of the tens of thousands of chondritic meteorites known to exist, there are only a few that do not fit into the conventional categories of classification. Because they are so unusual they have received the honorific classification “CH-UNGR” to indicate they’re ungrouped — they’re not readily classifiable. NWA 5717 belongs to this club as well and its chemical fingerprint informs us it originated from a previously unfamiliar parent body.
NWA 5717 is rarely available. This specimen has three cut faces and the rounded exterior is 90% covered in fusion crust — the result of burning through Earth’s atmosphere. For the more serious collector, this is a sample of some of the most primitive planetary material known.
33 x 45 x 27mm (1.33 x 1.75 x 1 in.) and 57.83 grams
Provenance: Macovich Collection of Meteorites / NYC
The article entitled "The Extra-Ordinary Chondrite: NWA 5717” published in the Journal of the Lunar and Planetary Conference accompanies this offering.