A not credible message about the discovery
of cometary material in the Egyptian desert
(Libyen Desert Glass area)
Unique chemistry of a diamond-bearing pebble from the Libyan Desert Glass
strewnfield, SW Egypt; Evidence for a shocked comet fragment
Jan D. Kramers et al. -- Earth and
Planetary Science Letters (2013), Volume 382, Pages 21–31
Published colored photo of the piece (30 gram)
"We have studied a small, very unusual stone,
here named “Hypatia”, found in the area of southwest Egypt where an
extreme surface heating event produced the Libyan Desert Glass 28.5
million years ago. It is angular, black, shiny, extremely hard and intensely
fractured. We report on exploratory work including X-ray diffraction,
Raman spectroscopy, transmission electron microscopy, scanning electron
microscopy with EDS analysis, deuteron nuclear reaction analysis, C-isotope
and noble gas analyses. Carbon is the dominant element in Hypatia, with
heterogeneous O/C and N/C ratios ranging from 0.3 to 0.5 and from 0.007
to 0.02, respectively. The major cations of silicates add up to less
than 5%. The stone consists chiefly of apparently amorphous, but very
hard carbonaceous matter, in which patches of sub-μm diamonds occur.
δ13C values (ca. 0‰) exclude an origin from shocked terrestrial coal
or any variety of terrestrial diamond. They are also higher than the
values for carbonaceous chondrites but fall within the wide range for
interplanetary dust particles and comet 81P/Wild2 dust. In step heating,
40Ar/36Ar ratios vary from 40 to the air value (298), interpreted as
a variable mixture of extraterrestrial and atmospheric Ar. Isotope data
of Ne, Kr and Xe reveal the exotic noble gas components G and P3 that
are normally hosted in presolar SiC and nanodiamonds, while the most
common trapped noble gas component of chondritic meteorites, Q, appears
to be absent. An origin remote from the asteroid belt can account for
"We propose that the Hypatia stone is a remnant
of a cometary nucleus fragment that impacted after incorporating gases
from the atmosphere. Its co-occurrence with Libyan Desert Glass suggests
that this fragment could have been part of a bolide that broke up and
exploded in the airburst that formed the Glass. Its extraordinary preservation
would be due to its shock-transformation into a weathering-resistant
The international reactions
to the statements in the article of the South African scientists are euphoric.
The investigated piece (it is a dark glassy fragment of 30 gram, and was
found in 1996 by the Egyptian geologist Dr. Aly A. Barakat in the area
of the silica glass) should be cometary material. This message in a short
time has already been inflationary widespread.
Because this euphoria I can not empathize,
I present my concerns at this point.
The conclusions of the South Africans
must be wrong.
In the entire area exist
no evidences of significant exo-terrestrial events. The
numerous crater-like structures
which are visible in this region (including the Libyan crater Oasis, BP
and Arkenu) belong to a large area with subvolcanic inventory from this
period before 28.5 million years. Included is the strewn field with the
Libyan Desert Glass. The Libyan Desert Glass
belongs as much to the inventory of this subvolcanic events such as other
specials (Jasper Mountain,
The emergence of the desert
glass, with an estimated total mass of about 1400 tons, is definitely
NOT caused by an airburst or an impact, but is an exceptional "volcanic"
glass. For the melting of sand masses at the surface by an airburst, there
were no conditions in the Oligocene period. The land surface was a rocky
ablation area. A sandy desert did not exist.
In contrast to the obsidian
is the desert glass not a conventional volcanic glass because it contains
96-99% SiO2. It must be presumed that it before 28.5 million years as
a pure glass melt along a deep fissure in the earth's crust flowed. Corresponding
flowing structures are visible in the glass. In the glass were identified
fourteen nano-sized crystalline, also polymorphs of diamond and graphite.
In this context also should
be classified the analyzed "shocked comet fragment". If we follow the
results of the investigation, then this material could be from the deep
and hidden interior of the earth.
|The arguments for cometary
origin of "Hypatia"
-It contains sub-micrometer diamonds
in an amorphous, carbon-dominated matrix.
-Carbon isotope data (δ13C~0) do not fit terrestrial coal or carbonaceous
-Argon, Kr and Xe isotope data show extraterrestrial origin different
are not convincing, because
ultimately our planet was created by aggregation of exo-terrestrial material
(even cometary material). What we know about the Earth's interior, is
not enough. Surprises are always possible. Predestined seems to be the
area in the southwestern Egyptian desert. It was affected by a magmatic
"hotspot" in the Tertiary period. The findings of "sub-micrometer diamonds
in an amorphous, carbon-dominated matrix" are a clear indication for the
origin of the material at great depths.
About the Occurrence
of micron-sized diamonds in the mullite-magnetite-silica glass boulders
in the Gilf Kebir area of western Egypt
M.A.G. Andreoli -- School of Geosciences, University
of the Witwatersrand, South Africa; Unpublished document (2017)
|"Dark grey mullite-magnetite-glass
melt rock (right); numerous diamonds were found in the polished, light
sandy grey slab (bottom left) but found absent in the core of the
dark, glassy patch." The location is south of the Silica area.
Comment: For me a puzzling, how the numerous diamonds were
be enclosed in the sedimentary rock. I believe it is a igneous dike-rock.
PIXE micro-mapping of minor
elements in "Hypatia", a diamond bearing carbonaceous stone from the Libyan
Desert Glass area, Egypt: Inheritance from a cold molecular cloud?
Matter originating from space, particularly if it represents
rare meteorite samples, is ideally suited to be studied by Particle Induced
X-ray Emission (PIXE) as this analytical technique covers a broad range
of trace elements and is per se non-destructive. We describe and interpret
a set of micro-PIXE elemental maps obtained on two minute (weighing about
25 and 150 mg), highly polished fragments taken from "Hypatia", a controversial,
diamond-bearing carbonaceous pebble from the SW Egyptian desert. PIXE
data show that "Hypatia" is chemically heterogeneous, with significant
amounts of primordial S, Cl, P and at least 10 elements with Z > 21 (Ti,
V, Cr, Mn, Fe, Ni, Os, Ir) locally attaining concentrations above 500
ppm. Si, Al, Ca, K, O also occur, but are predominantly confined to cracks
and likely represent contamination from the desert environment. Unusual
in the stone is poor correlation between elements within the chalcophile
(S vs. Cu, Zn) and siderophile (i.e.: Fe vs. Ni, Ir, Os) groups, whereas
other siderophiles (Mn, Mo and the Platinum group elements (PGEs)) mimic
the distribution of lithophile elements such as Cr and V. Worthy of mention
is also the presence of a globular domain (Ø S 120 lm) that is C and metals-depleted,
yet Cl (P)-enriched (>3 wt.% and 0.15 wt.% respectively). While the host
of the Cl remains undetermined, this chemical unit is enclosed within
a broader domain that is similarly C-poor, yet Cr–Ir rich (up to 1.2 and
0.3 wt.% respectively). Our data suggest that
the pebble consists of shock-compacted, primitive carbonaceous material
enriched in cold, pre-solar dust.
M. Andreoli et al.-- Article in Nuclear Instruments and
Methods in Physics Research, Section B, Beam Interactions with Materials
and Atoms (2015)
Publisher: Elsevier; DOI: 10.1016/j.nimb.2015.09.008
A comprehensive study of noble gases and nitrogen
in "Hypatia", a diamond-rich pebble from SW Egypt
G. Avice et al. -- Earth and Planetary Science Letters
(2015), Volume 432, Pages 243–253
|In 1996 a very unusual ~30 g sized
pebble was found in the Libyan Desert Glass strewn field where abundant
fragments of impact-related silica-rich glass are found. This brittle
black stone consists of ~70 wt. % carbon, and has a hardness comparable
to diamond, reminiscent of carbonados. These authors performed an
exploratory analytical study on "Hypatia", including XRD, SEM, Raman
spectroscopy, TEM, and analyses of C and noble gas isotopes motivated
by the fact that this stone was found in the area of the Libyan Desert
Glass (LDG). Noble gas isotope analysis is central to the study of
meteorites because these rocks formed from multiple components with
distinct noble gas isotopic signatures that help to constrain their
origin and evolution. Among these components, the so-called Q phase
dominates the budget of heavy noble gases (Ar, Kr Xe) in chondrites
originating from the asteroid belt.
Kramers et al. (2013) concluded that Hypatia is extra-terrestrial, based on
40Ar/36Ar ratios as low as about 40. They noted that O/C ratios (0.19
- 0.51) in Hypatia are higher than in chondritic Insoluble Organic
Matter (IOM). In addition, they reported that the trapped Ne, Kr,
and Xe in "Hypatia" indicate the occurrence of the nucleosynthetic
P3 and G components of presolar origin known from meteorites (Ott,
2014), while the Q (and HL) components ubiquitous in chondrites were
absent in "Hypatia". The combined evidence led them to conclude that
"Hypatia" did not originate in the asteroid belt where chondrites
likely formed. They suggested instead that it formed in a more external
region of the solar accretion disk, such as the Kuiper Belt, where
presolar components might be more abundant, i.e., that "Hypatia" could
be of cometary origin. They further proposed that the airburst of
the parent comet of "Hypatia" resulted in the formation of the Libyan
In this work we extend the study by Kramers et al. (2013) with isotopic
analyses of all five noble gases in several mg-sized fragments of
"Hypatia" in two different laboratories (CRPG Nancy, France and ETH
Zürich, Switzerland) and with a nitrogen isotope investigation performed
both at CRPG (Nancy) and IPG-Paris. We also describe results from
X-ray diffraction (XRD) experiments and transmission electron microscopy
(TEM) observations performed at the University of Jena (Germany).
An attempt to determine the oxygen isotopic composition in "Hypatia"
by the Nancy Cameca 1280 ion probe failed because of the reduced size
of oxygen-bearing phases and because of the presence of contaminants
and important amounts of water.
High resolution TEM image showing
the onion-shaped graphite (0001)gr in the surface of diamond (111)dia.
The absence of orientation relationship
suggests that graphite is here a product of retrograde annealing of
This new study confirms and provides
new evidence for the earlier conclusion that "Hypatia" is a fascinating
new type of extra-terrestrial material. In contrast to the exploratory
work reported by Kramers et al. (2013), we did find noble gases with isotopic
signatures closely resembling the Q component. We also found nitrogen
with an isotopic signature clearly distinct from primitive chondrites
and closely resembling those of various differentiated meteoritic materials.
In particular, we compare our data with noble
gas and nitrogen signatures in three known types of carbon-rich extraterrestrial
materials: carbon-rich veins in ureilite meteorites, graphite nodules
in iron meteorites, and carbon-rich lithologies in acapulcoites and lodranites,
and we discuss a possible link of "Hypatia" with each of these materials.