Meteorite**NWA 14261, L3-5**88.80 gram Slice, W/Rare Black Clasts!!

Description

Hello up for sale is NWA 14261 classified as a L3-5!!! This beautiful slice weighs 88.80 grams, has a nice polish on one side and, and many other unique features lke rare black clasts!!! Ordinary chondrite (L3-5) based on mineral chemistry and texture. The small clast similar to the host appears to be a low subtype 3 based on mineral chemistry.  Physical Characteristics: Cut faces are dark brownish gray with easily distinguished chondrules. Weathering is uneven, with replacement of metal along fractures. Metal is relatively abundant in some slices, including the one used for thin sectioning, while being mostly replaced in other slices. Slightly lighter-colored roughly equant clasts are visible in most slices; the largest is ~2 × 2 cm in area. Rare black clasts are visible in two of the six slices; the largest is ~2.5 × 1.3 mm in area. The thin section contains a host lithology that encloses a clast similar to the host lithology, part of one of the lighter-colored clasts, and two small black clasts. The host lithology is composed of distinct chondrules and chondrule fragments set in a dark matrix; zoned olivine is abundant in BSE images. A small (~5 × 2.5 mm across) clast similar in appearance to the host lithology is distinguished by textural discontinuities at its border. Chondrules are integrated with matrix in the lighter-colored clast, which contains plagioclase feldspar grains ?40 microns across; mineral chemistry indicates that the clast is equilibrated. The black clasts are entirely opaque in transmitted light. In BSE imaging, the black clasts are composed of a couple of cryptocrystalline chondrules and numerous rounded grains and clasts set in a fine-grained igneous-textured matrix. The section contains abundant sulfide; it forms partial rims around chondrules in the host lithology. Both the host lithology and equilibrated clast contain merrillite; the black clast contains chlor-apatite. The black clast also contains a silica polymorph and a few small grains of an aluminous spinel. This meteorite comes with a COA card. Thanks for your interest and take care.
Type 3
Designates chondrites that are characterized by abundant chondrules, low degrees of aqueous alteration, and unequilibrated mineral assemblages. Many of the low-Ca pyroxene grains are monoclinic and exhibit polysynthetic twinning. The type 3 chondrites may be divided into subtypes ranging from 3.00 (least metamorphosed) to 3.9 (nearly metamorphosed to type 4 levels). If primary igneous glass occurs in the chondrules, it belongs to type 3.
Chondrules
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By The Editors of Encyclopaedia Britannica Edit History
A small, rounded particle embedded in most stony meteorites called chondrites. Chondrules are usually about one millimetre in diameter and consist largely of the silicate minerals olivine and pyroxene. From textural and chemical relationships, it is clear that they were formed at high temperatures as dispersed molten droplets, which subsequently solidified and aggregated into chondritic masses. This process occurred in space in earliest times before the planets accreted. How the chondrules were melted, however, is not understood. It seems likely that dust particles or planetesimals already in existence were melted by high-energy events such as high-velocity collisions and splashed about as droplets that quickly cooled and crystallized.
Name: Northwest Africa 14261
This is an OFFICIAL meteorite name.
Abbreviation: NWA 14261
Observed fall: No
Year found: 2014
Country: (Northwest Africa)
Mass: 2.29 kg
Northwest Africa 14261 (NWA 14261)
(Northwest Africa)
Purchased: March 2014
Classification: Ordinary chondrite (L3-5)
History: One of several Northwest African whole stones purchased via online by DChenin from an American collector named Bill Hall who owns a Rock and Gem shop in Bend, OR. The stone was cut into slices; six were sent to Cascadia.
Physical characteristics: Physical Characteristics: Cut faces are dark brownish gray with easily distinguished chondrules. Weathering is uneven, with replacement of metal along fractures. Metal is relatively abundant in some slices, including the one used for thin sectioning, while being mostly replaced in other slices. Slightly lighter-colored roughly equant clasts are visible in most slices; the largest is ~2 × 2 cm in area. Rare black clasts are visible in two of the six slices; the largest is ~2.5 × 1.3 mm in area.
Petrography: (M. Hutson, A. Ruzicka, Cascadia): The thin section contains a host lithology that encloses a clast similar to the host lithology, part of one of the lighter-colored clasts, and two small black clasts. The host lithology is composed of distinct chondrules and chondrule fragments set in a dark matrix; zoned olivine is abundant in BSE images. A small (~5 × 2.5 mm across) clast similar in appearance to the host lithology is distinguished by textural discontinuities at its border. Chondrules are integrated with matrix in the lighter-colored clast, which contains plagioclase feldspar grains ?40 microns across; mineral chemistry indicates that the clast is equilibrated. The black clasts are entirely opaque in transmitted light. In BSE imaging, the black clasts are composed of a couple of cryptocrystalline chondrules and numerous rounded grains and clasts set in a fine-grained igneous-textured matrix. The section contains abundant sulfide; it forms partial rims around chondrules in the host lithology. Both the host lithology and equilibrated clast contain merrillite; the black clast contains chlor-apatite. The black clast also contains a silica polymorph and a few small grains of an aluminous spinel.
Geochemistry: Olivine Fa24.6±6.4, N=34 (host), Fa25.1±12.8, N=20 (small clast similar to host), Fa23.5±0.2, N=24 (equilibrated clast), Fa10.8±8.5, N=22 (black clast); Low-Ca pyroxene: Fs15.1±9.4Wo1.2±0.9, N=16 (host), Fs14.02±7.4Wo1.3±1.0, N=7 (small clast similar to host), Fs19.4±0.4Wo1.4±0.2, N=16 (equilibrated clast), Fs7.9±9.5Wo3.2±1.2, N=15 (black clast). Black clast: single spinel grain: Mg# 87.3, Cr# 0.6.
Classification: Ordinary chondrite (L3-5) based on mineral chemistry and texture. The small clast similar to the host appears to be a low subtype 3 based on mineral chemistry.
Specimens: Cascadia holds 201.5 g in six pieces, as well as a polished thin section; DChenin holds the main mass.
Data from:
MB110
Table 0
Line 0:
Place of purchase:online
Date:P March 2014
Mass (g):2291.3
Pieces:1
Class:L3-5
Fayalite (mol%):24.6 (host), 23.5 (eq. clast)
Ferrosilite (mol%):15.1±9.4 (host)
Wollastonite (mol%):1.2±0.9 (host)
Classifier:M. Hutson and A. Ruzicka, Cascadia
Type spec mass (g):201.5
Type spec location:Cascadia
Main mass:DChenin
Comments:Lab number CML 1375; submitted by Alex Ruzicka