9.33g Diogenite Gemmy Green HED Pyroxenite Achondrite Meteorite I NWA 7977

On Offer: 9.33g fragment of NWA 7977 an exceptionally beautiful pyroxenite Diogenite HED achondrite meteorite composed of over 95% green gemmy pyroxene crystals. Type: Diogenite (pyroxenite) Location: Northwest Africa Composition: 95% pyroxene Parent Body: Vesta or Vestoid Description: 9.33 gram piece of an amazing diogenite HED meteorite almost entirely made of gemmy green pyroxene crystals. This is arguably one of the most beautiful diogenites ever recovered. The HED Meteorite Clan: petrological evidence and data from NASA's Dawn mission indicate that nearly monomineralic ultramafic orthopyroxenite, olivine-bearing, and the much more rare harzburgitic, and dunite diogenites formed alongside each other. They likely originated as cumulates within localized magma chambers (plutons) situated across Vesta's lower crust and the lower-crust/upper-mantle transition zone. While the eucrites represent more evolved plagioclase rich mafic upper to middle zone crustal material. The howardites were formed by impact mixing of the diogenitic and eucritic material both in situ and during ejection events. The HED meteorites are so named for the three types of meteorites that comprise the group; Howardite, Eucrite and Diogenite. The Eucrite and Diogenite are meteorites with distinct chemistries, while the Howardite is a mix of the eucritic and diogenitic material. The HEDs are differentiated achondritic meteorites, thought to originate from the large differentiated asteroid 4 Vesta. Vesta is one of the only asteroids visible with the naked eye and low powered telescopes. The Vesta parent body origin for the HED clan of meteorites is considered to have been conclusively established for many years. However, the late Dr. John Wasson, a planetary science researcher from UCLA had long held that the HED meteorite clan originated from another unknown Vesta-like asteroid that was blown apart long ago. This is because we also find a class of iron meteorites with nearly identical oxygen isotopes as the HED clan. This along with other research lead Dr. Wasson to conclude the HED clan of meteorites come from another differentiated V-type asteroid that was in a cataclysmic collision liberating part or all of its metal core along with the HED meteorites. However, this hypothesis does not necessarily rule out the possibility that a "reaccreted" Vesta and the smaller V-type asteroids collectively known as Vestoids along with the HED meteorites and the isotopically paired irons were all once part of a much larger dwarf planet prior to a massive collision with another large body. While most researchers consider the case mostly closed on this debate, the paradox of isotopically paired core metal raised by Dr. Wasson's hypothesis has not been resolved. This leaves some to speculate that perhaps we still have more to learn about this fascinating clan of achondrite meteorites and even Vesta itself. What you get: 9.33 NWA 7977 diogenite meteorite specimen as shown, membrane storage/display box, & signed Certificate of Authenticity. We offer a 100% no questions asked 30 day return policy. SEE OFFICIAL METEORITICAL SOCIETY ENTRY BELOW Northwest Africa 7977 Basic information Name: Northwest Africa 7977 This is an OFFICIAL meteorite name. Abbreviation: NWA 7977 Observed fall: No Year found: 2013 Country: Morocco Mass: 3.4 kg Classification history: Meteoritical Bulletin: MB 102 (2013) Diogenite Recommended: Diogenite This is 1 of 442 approved meteorites classified as Diogenite. Comments: Approved 12 Sep 2013 Writeup Writeup from MB 102: Northwest Africa 7977 (NWA 7977) Morocco Purchased: 2013 Classification: HED achondrite (Diogenite) History: Purchased by Brahim Tahiri from a Moroccan hunter and sent to Sean Tutorow for classification, 2012. Physical characteristics: Numerous matching fragments of the original mass, friable with coarse grained gemmy green pyroxenes, some light tan desert coating present. Petrography: (C. Agee, UNM) Microprobe examination of a polished mount shows approximately 95% pyroxene, minor iron metal, chromite, troilite, and silica. Geochemistry: (C. Agee and N. Muttik, UNM) Low Ca-pyroxene Fs28.4±0.3Wo3.5±0.7, Fe/Mn=29±1 n=14. Classification: Achondrite (diogenite). Equilibrated, uniform pyroxene compositions. Specimens: Two pieces, 33.75 g and 22.1 g, including a probe mount, on deposit at UNM, Sean Tutorow holds the main mass. Data from: MB102 Table 0 Line 0: Place of purchase: Morocco Date: P 2013 Mass (g): 3403 Pieces: Many fragments Class: Diogenite Ferrosilite (mol%): 28.4±0.3 Wollastonite (mol%): 3.5±0.7 Classifier: C. Agee, UNM Type spec mass (g): 55.8 Type spec location: UNM Main mass: Sean Tutorow Comments: Field name G-382; submitted by C. Agee