On Offer: 10.58g slice of the ungrouped achondrite Ksar Ghilane 022 / 023 composed of more than 90% subcalcic diopside and exotic aubrite-like sulfides. This is a very special new achondrite meteorite, currently under classification at CCMS and other institutions, that is arguably the strongest candidate for a meteorite from the planet Mercury. This meteorite likely pairs with a similar magnesian diopside achondrite NWA 15915, but while the geochemistries, modality, and oxygen isotopic ratios are nearly identical, they seems to have slightly different textures with this meteorite having smaller overall crystal size than NWA 15915 resulting in remarkably different overall macroscopic appearance.

Officla name: Ksar Ghilane 022

*Under classification at CCMS with provisional name Ksar Ghilane 023

Class: Achondrite-ung

Parent Body: Unkown inner solar system differentiated body, with speculation for *Mercury

Description: 10.58 full slice of an amazing new ungrouped achondrite composed almost entirely of iron free subcalcic diopside. This meteorite is very friable (fragile), because of this we have decided to leave the finish natural with no stabilization or filling in of voids during the polishing process.

Dustin studying the new achondrite with the EMPA (microprobe) at
CU Boulder, working to better understand the exotic sulfides. So far
we have identified; oldhamite, alabandite, daubréelite, and caswellsilverite.

The EPMA results show this meteorite has no iron (Fs0-0.1) in the silicates, with exotic aubrite-like sulfide minerals that do contain Fe but not FeO with an XS chemical formula where X can be Ca, Mg, Mn, Fe, or Cr which can take the form of the exotic cubic sulfides; oldhamite, alabandite, daubréelite, and caswellsilverite, and others that are only found in the highly reduced enstatite chondrites, aubrites and rare reduced ungrouped achondrites, all of which likely formed in the inner solar system.

*These new magnesian (Fs0-0.1) clinopyroxenites are potentially thought to have the right chemistry and mineralogy to be from Mercury. Other meteorites with similarly iron depleted / magnesium rich mineralogies have been found to be too old to be from Mercury. Age dating of this meteorite may help resolve some of the questions surrounding its origins. It's unlikely we will ever be able to 100% confirm or refute these claims of possible Mercury origin, but having a formation date in line with those predicted for the crust of Mercury might go a long way to supporting it.

What you get: 10.58 slice of Ksar Ghilane 022 ungrouped achondrite meteorite specimen, as shown in a clear protective membrane box, with a signed Certificate of Authenticity.

I offer a 100% no questions asked 30 day return policy.

SEE OFFICIAL METEORITICAL SOCIETY ENTRY BELOW

Ksar Ghilane 022

Basic information

Name: Ksar Ghilane 022
This is an OFFICIAL meteorite name.
Abbreviation: KG 022
Observed fall: No
Year found: 2023
Country: Tunisia
Mass: 50 kg

Classification
history:

Recommended:

Achondrite-ung

This is 1 of 154 approved meteorites classified as Achondrite-ung.

Comments:

Approved 20 May 2024

Writeup

Writeup from MB 113:

Ksar Ghilane 022 (KG 022) 32.559°N, 9.508°E

Tatawin, Tunisia

Purchased: 2023

Classification: Ungrouped achondrite

History: Found in Tunisia in 2023. Purchased by Adam Aaronson in February and November 2023 from a Libyan dealer. Portions of the material were subsequently provided to Craig Zlimen at the Tucson Gem and Mineral Show in February 2024, and in turn acquired by Robert Ward, Brian Caress and Ben Hoefnagels.

Physical characteristics: A single large stone (25 kg) and many smaller pieces found with it. Most of the stones lack fusion crust and have mottled, dark and light gray granular exteriors. However, several pieces are partly coated by black fusion crust. The interiors of the stones have the appearance of equigranular aggregates of light gray and whitish grains.

Petrography: (A. Irving, UWS, and P. Carpenter, WUSL) The specimen is composed predominantly (>90 vol.%) of almost end-member augite (mostly as equant grains, mean grainsize ~1.5 mm) accompanied by minor enstatite and accessory Cr-troilite, daubreelite, alabandite and an Mn-Fe oxide phase. Enstatite occurs as small irregular inclusions or sparse fine lamellae within augite grains, and different macroscopic colors of the augite grains apparently reflect differing concentrations of sulfide inclusions. Some secondary calcite veins are present throughout.

Geochemistry: Augite (Fs_0.0-0.1Wo_39.4-42.3, N = 3), enstatite (Fs_0.1±0.0Wo_0.9-3.6, N = 3). Oxygen isotopes (K. Ziegler, UNM): analyses of acid-washed subsamples by laser fluorination gave, respectively, δ¹⁷O 3.018, 2.926; δ¹⁸O 5.781, 5.559; Δ¹⁷O -0.034, -0.009 per mil (all data linearized, TFL slope = 0.528).

Classification: Achondrite (ungrouped, Mg-rich clinopyroxenite). This meteorite is texturally and mineralogically very similar to ungrouped augite-rich achondrite NWA 15915. but does not exhibit the same degree of irrational exsolution of enstatite from the dominant constituent augite. Terrestrial pairing is further excluded by the different physical appearance of these two meteorites, different degree of weathering, and the fact that their purported find sites are hundreds of kilometers apart. Both of these meteorites may have some affinities to aubrites, but differ in being composed predominantly of almost Fe-free augite rather than enstatite.

Specimens: 41.3 g including one polished thin section at UWB; 677 g with Mr. R. Ward; 770 g with Mr. B. Caress; 674 g with Mr. B. Hoefnagels; 800 g with Mr. D. Dickens; remainder including the 25 kg main mass with Aaronson.

Data from:
  MB113
  Table 0
  Line 0:

State/Prov/County:	Tatawin
Place of purchase:	Libya
Date:	P 2023
Latitude:	32.559°N
Longitude:	9.508°E
Mass (g):	50000
Pieces:	many
Class:	Achondrite-ung
Shock stage:	low
Weathering grade:	low
Ferrosilite (mol%):	0.0-0.1; 0.1±0.1
Wollastonite (mol%):	39.4-44.1; 0.9-3.6
Classifier:	A. Irving, UWS, and P. Carpenter, WUSL
Type spec mass (g):	41.3
Type spec location:	UWB
Main mass:	Aaronson
Comments:	Work name M2322; submitted by A. Irving

SEE PROVISIONAL METEORITICAL SOCIETY ENTRY BELOW

Ksar Ghilane 023

Basic information

Name: Ksar Ghilane 023
This is a PROVISIONAL name.
It cannot be used in publications.

Abbreviation: KG 023
Observed fall: No
Year found: 2024
Country: Tunisia
Mass: 10 kg

Classification
history:

Recommended:

Unknown

Catalogs:

Provisional
info:

Name: Ksar Ghilane 023
Fieldname: MURC1
Origin/pseudonym: Tunisia
Purchased: Libya
Purchase or find date: Febuary, 2024
Lat/long: 32°33'31.4"N , 09°30'27.2"E
Mass: 10 Kg
Pieces: many
Specimens: 20g TCU
Description: An ungrouped magnesian clinopyroxenite achondrite with approximately >90% subcalcic diopside Fs0-0.1, <10% orthopyroxene Fs0-0.1, and >1% aubrite-like sulfides, oxygen plots to TFL, no olivine or plagioclase was found.
Info: This meteorite may pair to Northwest Africa 15915
Name assigned to: Dustin Dickens
Date assigned: 2024-05-03
Assigned by: Dustin Dickens

References:

Never published in the Meteoritical Bulletin

Find references in NASA ADS:
Find references in Google Scholar:

Geography:

Tunisia

Coordinates:
Recommended::	(32° 33' 31"N, 9° 30' 27"E)