Northwest Africa 10674 was purchased by Marc Jost as four pieces totaling 1,193 grams. It was classified by Irving and Kuehner as a polymict eucrite with a significant portion of metal-bearing H6 chondrite clasts with other asteroid debris.
Northwest Africa 2833 was a single 2,112 gram stone purchased in Erfoud, Morocco in 2005. It was classified as an L3.8 ordinary chondrite, S2, W3 by Wittke and Bunch and published in 2006.
Erg Chech 002 Achondrite-ung was found in the sand dunes of southwest Algeria in May 2020. Stones range in size from pebbles to a few weighing in the 4 kilogram range. Total weight could be about 45 kilograms. Classification was done by Tony Irving, University of Washington (Seattle), Paul Carpenter at Washington University (St. Louis) and Karen Ziegler at University
Northwest Africa 8781 C-ungr weighs 380 grams between several stones found together near Foum Zguid, Morocco, in July 2014. I find the reasoning for its classification informative. This is by the classifying scientist, Tony Irving. This specimen is not a CV3 chondrite (chondrule size much too small, no CAI), not a CK chondrite (no magnetite), not a CO3 chondrite (oxygen
Ozerki fell June 21, 2018 in Lipetsk oblast, European Russia, about 240 miles south of Moscow. More than a hundred stones were found totaling over 10kg. It is an L6 ordinary chondrite. Various shock levels are reported. The stone from which our thin section was made has been strongly shocked. It is a breccia of L6 clasts within solidified melt.
NWA 12774 angrite was purchased from a Mauritanian dealer in March 2019, changed hands in Ensisheim in June and we bought material in August to thin section. Angrites are rare ancient achondrites which crystallized on the parent body as early as only 4 million years after the condensation of CAI. Samples have a wide distribution of cosmic ray exposure ages
All the photos that follow were taken of this single thin section. Below are several more features in this
On the morning of June 29, 2017 the Serra Pelada meteorite arrived in a gold mining area of Amazonia with a fireball, smoke train, “detonations” and dust. A mass of about 6kg broke apart near a village school and was quickly scooped up and distributed among locals. About 4km east an electrician at a mining company site saw a similar
NWA 487 L/LL3.4 was distributed by Marvin and Kitty Killgore. They called it The Coffee Piece for its brown tint. I bought this thin section from them at the May 2003 Costa Mesa show. Even though an unequilibrated Type 3.4, it is apparent from its texture that its material has been recycled. Complex and compound chondrules, relict grains and aqueous
Our thin section maker deliberately varied the thickness to which he polished our Aguas Zarcas CM2 thin sections, from the standard 30 microns to thinner, sometimes much thinner. At the ‘proper’ thickness there are few crystalline features large enough to effectively span the thickness of the opaque, fine grain matrix. In transmitted light there is a lot of black. Thinner
Aguas Zarcas CM2 – Dust Mantles and Thin Thin Sections Read Post »
DaG 1040 CV3 contains a lot of metal and a variety of large chondrules and calcium-aluminum-rich inclusions. Here is a selection of smaller objects, all found in a single thin section. The largest is a one half millimeter diameter chondrule. All photos were taken in cross-polarized light.
NWA 3118 is a reliably feature rich CV3. It is a pleasure to view in thin section because of its dark uncluttered matrix and large well defined chondrules, AOAs and CAIs. Here is a gallery from a single thin section. All photos taken in cross-polarized light.
NWA 7203 was a single 107 gram fusion crusted stone from Morocco. It was purchased by Luc Labenne in Tucson in 2011. This meteorite is a quenched angrite from a surface or near surface magma on the angrite parent body. Its texture is dendritic, a result of rapid cooling of the magma. The branches are composed of olivines and feldspar.
Serra de Magé is an unbrecciated cumulate eucrite. It has a high feldspar content for a eucrite, ~65-70 volume %. The feldspar is anorthite. Pyroxene is orthopyroxene with often complex exsolution lamellae of augite sometimes described as appearing wormlike. Sample is 13mm wide. Cross-polarized light (XPL). Some opaques are visible. Note bits of fusion crust along the sloping upper edge.
