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View a list
of fine Howardites |
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What are Howardites?
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Howardites are a rather rare group of
achondrites that appear to be the link between eucrites and diogenites
. Howardites are polymict breccias.
They contain crystals and irregular clasts of eucrite and diogenite,
they are polymict breccia. Howardites are thought to have originated
from the surface of Vesta.
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NWA
1929 howardite
NWA 1929, 1 piece was collected in
5/2003 with a TKW of 922.3 grams
(22.02g deposit material at NAU)
5.5 gram end
cut 6x5x1cm w.crust 191$; 2g slice 23x22mm $76, 0.2g slice 4x5mm with crust
$10 |
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NWA 3117 Howardite
available @$20/gr 0,6g;
76 gram endcut |
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NWA 3078
highly beautiful!
Meteoritical
Bulletin: Howardite
Recommended:
Eucrite-pmict
Writeup,
from MB 88:
Northwest Africa 3078
One single stone
of 733 g mostly covered with fresh fusion crust
was found in
winter 2002/2003 by an anonymous finder in the Western Saharan desert.
Classification and mineralogy (A. Greshake and M. Kurz, MNB): polymict
breccia dominated by
often chemically
zoned orthopyroxene fragments set into a clastic
matrix. Other
types of fragments include large blocky pagioclase,
Other types of
fragments include large blocky pagioclase, pigeonite with augite exsolution
lamellae, and unusual
orthopyroxene
and sulfide-rich clasts; orthopyroxene, Fs23.8- 47.7Wo1.4-3.3, plagioclase,
An90.9; pigeonite, Fs25-40.3Wo5.1-6.3; augite, Fs17.7-29.6Wo27.3-42.4; minor
phases are sulfides, FeNi metal,
chromite, and
Al-Ti-rich chromite; low degree of shock; low degree of weathering.
Specimens: Main mass with anonymous
finder; type
specimen 20 g plus one polished thin section MNB.
Classification and mineralogy: (Dr.A. Greshake and M. Kurz): Berlin,
Humboldt Univ; Germany
! Available
slices show unusual inclusions!
1.1g slice sold,
1.3g slice 18x20mm; 7.04g slice 43x52mm |
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NWA
2060
Howardite
A 985 g, very
fresh howardite with shiny fusion crust, was purchased
in Rissani, July
2003. Classification and mineralogy (T. Bunch
and J. Wittke,
NAU):
a howardite of unusual characteristics.
Fine-grained
and powdery, average clast and mineral grain size is
< 2mm with few
clasts > 3 mm. Clast modes: diogenites, 74 vol.
%; eucrites 20
vol. % (12 % cumulate, 8 % basaltic); anorthositic-
like clasts, 3 %;
shock melt clasts. 2 %, and opaques, 1%.
Diogenite
orthopyroxene, Fs35.6-38.8Wo2.3-4.2; plagioclase, An 87;
chromite, Cr/(Cr+Al)
= 0.81; metal, Ni = 0.67 wt %. Melt inclusions
in opx contain
Ca-rich pyroxene, Fs33.3Wo37.5; phosphate,
silica phase, and
K-rich glass. Plagioclase-pyroxene cumulates,
Fs38.2Wo21;
plagioclase, An86.
eucrite textures
include recrystallized,
granular, ophitic,
subophitic, and variolitic
(Fs31.6Wo7 and
Fs61.8Wo33). Plagioclase-rich clasts have 95 vol.%
plagioclase
(An96.1). Mildly shocked; no apparent oxidation or Fe
staining.
Specimens: 26 g,
NAU:
main mass.
Boswell.
GS $12; BB $19; 2.1g slice 25x22mm
$120, 0.4g slice 7x4mm
with crust $27 |
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Howardite / Eucrite, Name:
DaG 411
Found May 13th
1999.Achondrite (Howardite). A single 400 g howardite of fresh condition was
found by a person prospecting for meteorite.interesting
interior . Originally DaG 411 was classified as an eucrite because small
research samples can cross only the eucritic zone inside the Howardite
available thin slices with crust:
Bug Box $12;
thin slice:
0,52g
$73;
2.65g
23x17mm $330;
0.940g
thin slice
16x15mm $100;
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Howardite / Eucrite,
DaG 671
Found 1999. Quite
Fresh; interesting interior |
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Howardite - DaG 779
One fragmented meteorite of TkW 18,8 kg was found
20th of November 1999 in the desert and is the largest known howardite
find, listed, with shock (S2) , weathering (W1) and type classification,
basic data and mineral analysis, plagioclase: An74.6-96.3, avg. An89.5
Or0.5.
Bug Box $19;
thin
slice: 0,5g
$54 thin slice: 1,1g $149
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Howardit - Dho 018
 
Bug Box $19; 0,21gr ultrathin slice; endpiece |
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You can find some howardites that were
classified as polymict eucrite under:
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