header
  MetSoc Home            Publications            Contacts  
Search the Meteoritical Bulletin Database
Last update: 15 Apr 2024
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:
Limit to approved meteorite names
Search text:  
Northwest Africa 16478
Basic information Name: Northwest Africa 16478
     This is an OFFICIAL meteorite name.
Abbreviation: NWA 16478
Observed fall: No
Year found: 2013
Country: (Northwest Africa)
Mass:help 477 g
Classification
  history:
Recommended:  Ureilite    [explanation]

This is 1 of 660 approved meteorites classified as Ureilite.   [show all]
Search for other: Achondrites, Ureilites
Comments: Approved 30 Mar 2024
Writeuphelp
Writeup from MB 113:

Northwest Africa 16478 (NWA 16478)

(Northwest Africa)

Purchased: 2013 May 16

Classification: Ureilite

History: A single 477 g fresh black stone was purchased by Zuokai KE from a Moroccan dealer Mohamed Aid in May 2013 during Changsha Mineral Show in China.

Physical characteristics: A single stone of 477 g is ovoid-shaped and has partially broken black surface with the remnants of fusion crust.

Petrography: Observations under optical microscope and SEM images show that the meteorite is composed of olivine (~35 vol.%), pigeonite (~50 vol.%), carbonaceous interstitial materials (~15 vol.%), and minor amounts of Fe-Ni metals, sulfides and weathering products. No chondrule structures were observed in the sample. Olivine grains, sub- to anhedral and ranging from 0.3-1.5 mm in size, have obvious magnesium reduction zones with a width of ~0.05 mm; while the anhedral pigeonite garins are smaller (about 0.3 mm) without reduction zones. The contacts of silicate grains at places have 120° triple junctions. The carbonaceous interstitial materials are black, mainly appear at the boundaries or voids of silicate grains. Fe-Ni metals and sulfides are mainly distributed in the boundary of olivine and pigeonite grains or along cracks.

Geochemistry: Olivine (cores Fa18.2±2.1, CaO 0.58±0.09 wt%, Cr2O3 0.31±0.01 wt%, N=4; rims Fa10.6±5.5, N=4). Pigeonite (Fs14.1±1.2Wo9.1±0.3, N = 3)

Classification: Ureilite

Specimens: Zuokai KE holds the main mass of 477 g. In total, 27 g of type specimen (including one polished thin section) is on deposit at PKU.

Data from:
  MB113
  Table 0
  Line 0:
Place of purchase:Changsha, China
Date:P 2013 May 16
Mass (g):477
Pieces:1
Class:Ureilite
Shock stage:U-S1
Weathering grade:moderate
Fayalite (mol%):18.2±2.1 (N=4)
Ferrosilite (mol%):14.1±1.2
Wollastonite (mol%):9.1±0.3
Classifier:S. Qin and M. Miao, PKU
Type spec mass (g):27
Type spec location:PKU
Main mass:Zuokai KE
Comments:Submitted by Shan Qin, Mengqi Miao
Institutions
   and collections
PKU: Peking University, Beijing 100871, China, China; Website (institutional address; updated 14 Oct 2023)
Catalogs:
References: Published in Meteoritical Bulletin, no. 113, in preparation (2024)
Find references in NASA ADS:
Find references in Google Scholar:
Photos:
CreditPhotos
Public domain photographs:
Shan Qin                  
Geography: 
Coordinates:Unknown.

Statistics:
     This is 1 of 9699 approved meteorites from (Northwest Africa) (plus 1854 unapproved names)

Direct link to this page