2025年2月8日 · Name: Northwest Africa 2999 This is an OFFICIAL meteorite name. Abbreviation: NWA 2999 Observed fall: No Year found: 2004 Country: (Northwest Africa) Mass: 392 g Classification

As matters stand now, NWA 2999 appears to be a very unusual angrite meteorite. Only Angra dos Reis (stone) (~90% fassaite) and NWA 8535 , a dunitic angrite (~90% olivine), differ as substantially from the angrite mineralogical norm (subequal anorthite, fassaite, and olivine).

data for NWA 2999. These data confirm an angrite ori-gin of NWA 2999, but also indicate differences in chemistry and composition of NWA 2999 to other angrites, making this a unique meteorite. Texture, mineralogy and oxygen isotopes: NWA 2999 has an overall plutonic, polygonal-granular tex-ture (similar to Angra dos Reis and LEW 86010), but

2021年3月3日 · NWA 2999 is a coarse-grained, allotriomorphic-granular stone that displays clear signs of brecciation. It is composed of Al, Ti-bearing pyroxene, plagioclase, Ca-rich olivine, and Cr-rich spinel along with kamacite and troilite as accessory phases (Kleine et al. 2012).

Noble gases in the five angrites Northwest Africa (NWA) 1296, 2999, 4590, 4801, and 4931 were analyzed with total melting and stepwise heating methods. The noble gases consist of in situ components: spallogenic, radiogenic, nucleogenic, and fission.

2007年3月1日 · Noble gases in the five angrites Northwest Africa (NWA) 1296, 2999, 4590, 4801, and 4931 were analyzed with total melting and stepwise heating methods. The noble gases consist of in situ components: …

鈦輝無粒隕石是 玄武岩 類的 岩石，通常有直徑可以達到2.5厘米（0.98英寸）的 多孔狀結構 的 孔隙。 它們是最古老的 火成岩 岩石，大約在45億5000萬年形成 結晶。 通過比較鈦輝無粒隕石與幾顆 主帶小行星 的 光譜 反射能力，已經確認了兩個可能的母體：小行星 (289) Nenetta 和 (3819) 羅賓遜。 其他的科學家聲稱鈦輝無粒隕石也可以來自 水星 的 噴發。 目前只有12顆隕石歸類為鈦輝無粒隕石。 此群的樣本，安格拉杜斯雷斯隕石，是在1869年被觀測到墜落，重量為1.5公 …

Angrite NWA 2999: A group of stones (totaling at least 2.4 kg) found in Northwest Africa in 2004 represent the tenth known example of the enigmatic angrite meteorites.

2007年3月1日 · NWA 2999 is classified as an angrite. Bulk chemical analyses show high Mg, Cr, Ni, Co, Ir, and Au, unlike any other angrite. This meteorite contains more than 50% of a meteoritic component, or of...

2005年1月1日 · Angrite NWA 2999: A group of stones (totaling at least 2.4 kg) found in Northwest Africa in 2004 represent the tenth known example of the enigmatic angrite meteorites.