header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 30 Nov 2019
Search for: Search type: Search limits: Display: Publication:
Names
Text help
Places
Classes
Years
Contains
Starts with
Exact
Sounds like
NonAntarctic
Falls  Non-NWAs
What's new
  in the last:
Include past classifications in search
Limit to approved meteorite names
Search text:  
Northwest Africa 12678
Basic information Name: Northwest Africa 12678
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 12678
Observed fall: No
Year found: 2018
Country: (Northwest Africa)
Mass:help 228 g
Classification
  history:
Recommended:  H5-melt breccia    [explanation]

This is 1 of 20 approved meteorites classified as H5-melt breccia.   [show all]
Search for other: H chondrites, H chondrites (type 4-7), Melted chondrites, Ordinary chondrites, and Ordinary chondrites (type 4-7)
Comments: Approved 27 Jun 2019
Writeuphelp
Writeup from MB 108:

Northwest Africa 12678 (NWA 12678)

(Northwest Africa)

Purchased: 2018

Classification: Ordinary chondrite (H5, melt breccia)

History: Purchased by Larry Atkins from Morocco in December 2018.

Physical characteristics: Two identically appearing pieces; saw-cut surfaces reveal a fragmental breccia, large portions of which consist of vesiculated melt rock. Significant oxidation visible.

Petrography: (C. Agee, UNM) Microprobe examination shows many melt rock veins crosscutting H5 chondrite domains with texturally equilibrated chondrules and recrystallized matrix. Plagioclase grain size up to 50 μm in diameter.

Geochemistry: (C. Agee, UNM) Olivine Fa19.5±0.2, Fe/Mn=40±1, n=10; low-Ca pyroxene Fs16.9±0.2Wo1.5±0.4, Fe/Mn=22±2, n=6; plagioclase Ab85.2±1.3An11.3±0.2Or3.5±1.4, n=3; shock melt SiO2=43.8±3.2, TiO2=0.13±0.02, Al2O3=2.9±0.6, Cr2O3=0.58±0.04, MgO=30.7±5.6, FeO=17.0±4.7, Mn=0.35±0.04, NiO=0.07±0.05, CaO=1.9±0.5, Na2O=1.0±0.2, K2O=0.21±0.13 (all wt%), n=4.

Classification: H5-melt breccia

Specimens: 27.5 g including a probe mount on deposit at UNM, Larry Atkins holds the main mass.

Data from:
  MB108
  Table 0
  Line 0:
Place of purchase:Morocco
Date:P 2018
Mass (g):228.2
Pieces:2
Class:H5-melt breccia
Shock stage:S4
Weathering grade:W3
Fayalite (mol%):19.5±0.2
Ferrosilite (mol%):16.9±0.2
Wollastonite (mol%):1.5±0.4
Classifier:C. Agee, UNM
Type spec mass (g):27.5
Type spec location:UNM
Main mass:Larry Atkins
Comments:Field name LA-11; submitted by C. Agee, UNM
Institutions
   and collections
UNM: Institute of Meteoritics MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 USA, United States; Website (institutional address; updated 12 Feb 2015)
Catalogs:
References: Published in Meteoritical Bulletin, no. 108, in preparation (2019)
Find references in NASA ADS:
Find references in Google Scholar:
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 7035 approved meteorites from (Northwest Africa) (plus 2000 unapproved names)

Direct link to this page