Texture N°4 meteorite Nakhla

the specimen attached here is about 12 x 5 x 5 cm in dimension and has distinctive "blueberry" spherules. these spherules are also purple, black, and tan colored. the rock seems to match Nakhla, NWA 998, NWA 5790, Governador Valadares and other "Nakhlites".

I have yet to find any high-quality images (most are blurry) of Nakhla or of other rocks claimed to be nakhlites. please give me feedback.

Remerciements https://www.mindat.org/forum.php?read,98,331680,331848

New Haven, CT
Meteorite: Chassigny
Location: Chassigny, Haute Marne, France
Fell: October 3, 1815 08:00
Type: Chassignite (SNC)

In 1815, a stone was observed to fall from the sky after loud sonic booms were heard. Although it was estimated that the meteorite originally weighed about 4,000 grams (~9 pounds), there is only about 570 grams preserved of the meteorite today. Chassigny is distinctly different from the other SNC's, so it has been assigned its own signature subgroup, chassignite, to distinguish it from the shergottites and nakhilites.

chas_s.gif44K
Small fragment of the Chassigny Meteorite
One of the few pieces of Chassigny in a private collection
Copyright 1995 Ron Baalke
Chassigny is the only meteorite in classified as a chassignite. The meteorite pictured directly above is a small fragment from the collection of Ron Baalke.

chas2_s.jpg26K
Another fragment of the Chassigny Meteorite
Photo courtesy of Martin Horejsi
chas3.jpg16K
Thin section of Chassigny shown in polarized light
Photo courtesy of Johnson Space Center
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MARTIAN METEORITES COMPARATIVES TEXTURES METEORITE CHIZE DE MARS

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Northwest Africa 998 (Martian (nakhlite))

Direct link to photo: http://www.encyclopedia-of-meteorites.com/.../17921_6091...
https://www.lpi.usra.edu/meteor/get_original_photo.php...
Northwest Africa 998 (Martian (nakhlite))Northwest Africa 998
Basic information Name: Northwest Africa 998
This is an OFFICIAL meteorite name.
Abbreviation: NWA 998
Observed fall: No
Year found: 2001
Country: (Northwest Africa)
Mass:help 456 g
Classification
history:
NHM Catalogue: 5th Edition (2000) Martian (shergottite)
Meteoritical Bulletin: MB 87 (2003) Martian (nakhlite)
MetBase: v. 7.1 (2006) Nakhlite
Recommended: Martian (nakhlite) [explanation]

This is 1 of 19 approved meteorites classified as Martian (nakhlite). [show all]
Search for other: Martian meteorites
Writeuphelp
Writeup from MB 87:
Northwest Africa 998
Algeria or Morocco
Purchased 2001 September
Martian meteorite (nakhlite)
A. and G. Hupé (xHupé) purchased, from dealers at the Tucson Gem and Mineral Show in 2002 February, the main mass from a 456 g stone that had been acquired at an unspecified site in western Algeria or eastern Morocco in 2001 September. Dimensions before cutting: 72 mm by 65 mm by 48 mm. Classification and mineralogy (A. Irving and S. Kuehner, UWS): a friable, dark green rock with minor orange-brown alteration products that probably are of pre-terrestrial origin. It is composed mainly of subhedral, olive-green, complexly zoned subcalcic augite (Fs22Wo39) with subordinate yellow olivine (Fa64), orthopyroxene (Fs49Wo4), interstitial plagioclase (Ab61Or4 containing 0.1 wt% SrO, and exhibiting normal birefringence), titanomagnetite, chlorapatite and pyrrhotite. The overall texture is that of a hypabyssal, adcumulate igneous rock, and the apparent crystallization sequence is olivine, orthopyroxene, titanomagnetite, augite, apatite, plagioclase. There is a weak preferred orientation of prismatic pyroxene crystals, many of which have very distinctive zoning, with cores of augite surrounded by irregular, inverted pigeonite rims (now consisting of orthopyroxene with fine augite lamellae). Trains of tiny melt inclusions are present along healed fractures within pyroxene; microprobe study confirms that most of these are K-Na-Al-bearing silicate glass, but some are intergrowths of glass and Fe-bearing carbonate, which may represent quenched immiscible silicate-carbonate liquids. Symplectitic intergrowths of titanomagnetite and low-Ca pyroxene are present at grain boundaries between large, discrete olivine and titanomagnetite grains, but are not present around chromian titanomagnetite inclusions within olivine. These observations suggest that a pre-terrestrial oxidation process produced the symplectites, and involved high temperature, deuteric fluid infiltration along grain boundaries; such fluids also may have produced the irregular pigeonitic rims on augite crystals. Secondary (probably pre-terrestrial) ankeritic carbonate, K-feldspar (some Fe-bearing), serpentine (?), calcite and a Ca sulfate are present on grain boundaries and within cracks in augite. Oxygen isotope composition (D. Rumble, CIW): replicate analyses of acid-washed augite by laser fluorination gave δ18O = +3.9 ± 0.2‰; δ17O = +2.4 ± 0.1‰; ∆17O = +0.30 ± 0.02‰. Specimens: type specimens, 20 g, UWS, 20 g, FMNH, and two polished thin sections, UWS; main mass, xHupé.
Data from:
MB87
Table 8
Line 32:
Origin or pseudonym: Morocco/Algeria
Place of purchase: Tucson, Az
Date: Sep 2001
Mass (g): 456
Pieces: 1
Class: Martian
Classifier: A. Irving, UWS
Type spec mass (g): 40
Main mass: ROM
Comments: see separate entry
Plots: O isotopes:
Institutions
and collections FMNH: Department of Geology The Field Museum of Natural History 1400 South Lake Shore Drive Chicago, IL 60605-2496, USA, United States; Website (institutional address; updated 16 Nov 2011)
ROM: Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada (institutional address; updated 18 Oct 2011)
UWS: University of Washington, Department of Earth and Space Sciences, 70 Johnson Hall, Seattle, WA 98195, United States (institutional address; updated 15 Jan 2012)
CIW: Carnegie Insitution Washington, Geophysical Laboratory, 5251 Broad Branch Rd., NW, Washington DC 20015, United States (institutional address)
xHupé: (old address—now see GHupé or AHupé) G. and A. Hupe, 2616 Lake Youngs Court SE, Renton, WA 98058., United States (private address)
Catalogs:
References: Published in Meteoritical Bulletin, no. 87, MAPS 38, A189-A248 (2003)
Find references in NASA ADS: NASA ADS
Find references in Google Scholar: Google Scholar
Photos:
Credit Photos
Photos uploaded by members of the Encyclopedia of Meteorites.
(Caution, these are of unknown reliability)
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Geography:
Coordinates: Unknown.

Statistics:
This is 1 of 5736 approved meteorites from (Northwest Africa) (plus 2073 unapproved names)
Also see:
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Revision
history:
Revision history This lists importa – à texture 10/02 10/01 10/03 .