Dho 378 - 0,050gr slice
One fresh martian meteorite of 15g covered with almost 100% complete fresh black fusion crust was discovered on June 17th 2000 in a desert area by anonymous finder.
It turned out to be one of the most interesting and unique meteorite discoveries ever. Dho 378 is only one of four Calcium poor Martian Meteorites in the world (beside ALH84001, Chassigny, and NWA 998) .
Due to the presence of titanomagnetite the Dhofar 378 belongs to the rare titanomagnetite-bearing basaltic shergottite group.
There is an extremely high possibilty that this glassy Martian rock will give us the possibility to get insight into intercrustal magmatic differentiation process on Mars and give hints for potential mining (Ti) missions on Mars.
The high Fs content of the pyroxenes(Fs 40 to 93) and the high proportion of feldspar suggest that Dho 378 is a late Martian magmatic differentiate.
Among basaltic shergottites Dho 378 represents the most evolved Martian magmatic liquid composition.
Dho 378 experienced a 2 stage thermal history. A secondary melting at extremely high temperatures was followed by slow cooling (what the recrystallization of various plagioclas segments seem to confirm). Polished thin sections show that Dho 378 consists mainly of Maskelynite, plagioclase glass, with minor minerals of hedenerbergite and ferroan clinopyroxenes (augite and pigeonite) pyrox-ferroite, fayalite, silica, titanomagnetite, ilmenite, sulfide, phosphate, and rhyolitic glass as the main minerals.
Studies on Dhofar 378 undertaken by J. PARK and K. NAGAO, 1Laboratory for Earthquake Chemistry, Graduate School of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan proved that heavy fractionation occurred on Ne isotopic composition in Martian atmosphere.
Neon is highly enriched in DHO 378 compared to those of other shergottites.The trapped 20Ne is not enriched in the plagioclase glass
phase but in pyroxene-rich phase of this meteorite (J. PARK and K. NAGAO,2006 see:
NEW INSIGHTS ON MARTIAN ATMOSPHERIC NEON FROM MARTIAN METEORITE, DHOFAR 378: http://www.lpi.usra.edu/meetings/lpsc2006/pdf/1110.pdf)
In terms of mineralogy Dhofar 378 is more similar to LA 001/002 than to other members of shergottite groups.
CRYSTALLIZATION EXPERIMENT; IMPLICATIONS FOR THE CRYSTALLIZATION OF LOS ANGELES 001 AND DHO 378.
Similar to Los Angeles the Cr is very low. Dho 378 is the first shergottite with a positive Eu anomaly. The amount of phosphates, mainly whitlockite, is only 1 % as deduced from the REE abundances. The host mineral of the REEs in all shergottites is whitlockite, which controls the bulk rock REE concentrations. Whitlockite has a negative Eu anomaly. But, in the case of Shergotty, Zagami, and Los Angeles the absolute Eu content of whitlockite is high enough to compensate the positive Eu anomaly of maskelynite. Only in Dhofar 378, with about 50 times more plagioclase glass than whitlockite, we observe a positive Eu anomaly.
Extensive research was done by some of world's most famous scientists in Japan. (Ikeda Y. , Takeda H. et al.) 2000/2001 and in Germany G. Dreibus, F. Wlotzka, W. Huisl, E. Jagoutz, A. Kubny and B. Spettel, Max-Planck-Institut f. Chemie, P.O. Box 3060, D-55020 Mainz,Germany.
The mineralogical composition of the stone is; clinopyroxenes (49 vol.%), plagioclase glass (47 vol.%), titanomagnetite including ilmenite (3 vol.%) and phosphates (1 vol.%). Dho 378 is enriched in Na, Sr (Table) and feldspar compared to other shergottites.
U-Pb isotope measurements on ultraclean mineral separates are under way.
Dho 378 is heavily shocked and the plagioclase glass often shows flow structures, evidence that it was melted. The center of these melts are quenched to alkali enriched glass while the rims crystallized to Ca enriched plagioclase. Raman spectroscopy confirms these features. This zoned plagioclase glass offers the opportunity to determine the age of the shock event!
Quenched melt textures involving other minerals are also found, but little mixing occurred.
The oxygen isotopic composition of the stone was obtained by T.K.Mayeda and R.N.Clayton. The result is: delta O 18 = +4.46 permil, and delta O 17 = +2.52 permil, indicating that this stone is within the range of previously analyzed Martian meteorites.
Deposit Material: Max-Planck-Institute Germany 2.74g plus PTS and 1 PTS in Japan.
(image above and/or below is just a sample image - Actual sample you receive will look moderately different but is appr. of same quality
.If you like a photo first kindly email to us)!