What tell us the finds of carbon and diamonds
in the LDG, other glassy melts and breccias in the Silica-strewnfield
in the Egyptian Great Sand Sea
Upload: April 2018
Diamond is a solid form of carbon
with a cubic crystal structure. Most of them were formed in enormeus
depths in the Earth's mantle. Under high pressure and temperature, carbon-containing
fluids dissolved minerals and replaced them with diamonds. Diamonds are deposited
in igneous rocks known as kimberlites and lamproites
carried to the surface by volcanic eruptions. Extraterrestrial diamonds, mostly
of a microscopic size, are found in carbonaceous chondrites.
In the strewnfield of the Libyan Desert Glass (LDG) is hidden
not only the secret of the creation of this unique glass itself, but also
the origin of some accumulations of carbon/graphite and diamonds /micro-diamonds
embedded in glassy melts within breccias. In the meantime it can be ruled
out that these materials are of extraterrestrial origin. To convincing are
indications for a connection with the widespread volcanism in the region.
Here we have diamonds that have been transported from the earth's mantle to
the earth's surface.
The following locations are known so far, and they should not be the last.
Unfortunately, all the ludicrous interpretations of the elaborate investigations
point in the totally wrong direction, as the citations listed below from the
publications prove. The find of kimberlite (Location
7) bring the impact theory now the death.
inclusions, polymorphs of graphite and diamond
in a carbonaceous matrix
Breccia 3 (Qaret-el-Hanash)
25°04' / 25°55'
a glassy matrix
Debris in Paleosol
3.8 km SSW
of 25°18.11' / 25°29'
and carbonaceous debris
the Silica area
Dark grey mullite-magnetite-glass
melt rock with numerous diamonds
Zerzura (Kimberlite pipe)
( + micro diamonds)
in Libyan Desert Glass: Effect of microgravity environment
C. Patuelli, R. Serra, S. Coniglione, M. Chiarini
Microgravity and Space Station Utilization, vol. 3, no. 4, 2002
"Samples of Libyan Desert Glass were analyzed by
X-ray micro-diffraction technique. It was identified fourteen nano-sized
crystalline LDG phases with different colours: Coesite, tridymite,
stishovite, baddeleyite, huttonite, yttrium, moissanite, platinium,
polymorphs of diamond and graphite.
The four praphite polymorh phases found in LDG samples can be explained
by taking into account that the graphite came from the earlier history
of the material. The element platinum is extremely scarce in most crustal
rocks. The origin of platinum is from ultra-mafic igneous rocks. Its melting
point is 1775 °C. The zircon oxide mineral Baddeleyite is the product
of the decomposition of zircon at 1775° - 1900°C. Moissanite is a natural
silicon carbide (SiC). Huttonite is a low-temperature and low-pressure
The identification of nine highbaric phases, the
presence of hexagonal diamond with four phases of graphite polymorphs,
as well as huttonite and baddeleyite, confirm that LDG formed by "shock
metamorphism" at very high pressure and temperature. The nano-sized crystalline
phases revealed point out that LDG rapidly solidified.
Preliminary X-ray micro-diffractometry analyses were presented at the
“Silica 96” workshop (Patuelli, 1997). High pressure and high temperature
phases were identified: including samarium, germanium 12T, thorium beta
(this beta phase occurs only at a temperature above 1350°C) and stishovite,
which is a high temperature and pressure form of SiO2."
liquid immiscibility and graphite ribbons in Libyan Desert Glass
G. Pratesi, C. Viti, C. Cipriani, M. Mellini
Geochimica et Cosmochimica Acta, March 2002
"Transmission electron microscopic (TEM) investigation of the dark (brown
or bluish) streaks occurring in Libyan Desert Glass reveals the common
presence of small glass spherules. The spherules, mostly 100 nm
in size, are homogeneously dispersed within the silica-glass matrix. The
complete absence of electron
diffraction effects confirms their amorphous nature. The spherules are
Al-, Fe- and Mg-enriched with respect to the surrounding silica matrix
and their (Mg+Al+Fe) : Si ratio is close to 1. The silica-glass matrix
and amorphous spherules form an emulsion texture (i.e., globules of one
glass in a matrix of another glass), which originates from silicate-silicate
The silica glass also contains carbonaceous inclusions
consisting of 5–50 nm thick, polygonalized graphite
ribbons that form closed structures up to 200 nm in diameter.
Rare carbon-bearing inclusions randomly occur within the silica-glass
matrix. Their presence is ubiquitous and not limited to the regions with
dark streaks. C-bearing inclusions produce an evident C peak in the EDS
spectra. The inclusions consist of ring-shaped polygonalized ribbons,
5–50 nm thick, typically forming closed structures with an overall diameter
of ~200 nm. Their SAED patterns consist of rings with d-spacings of 3.35,
2.09 and 1.67 A: these values correspond to graphite (3.36, 2.13-2.03,
1.678 A, JCPDS 23-64). Lattice imaging shows 3.35 A polygonized (002)
lattice fringes. The fringes are quite regular, thus indicating good structural
order with no evidence of deformation or defects. Dark vertical bands
are evident at the polygonal edges and are interpreted as Moire textures."
Probably debris of
First paper by Aly Barakat, the discoverer of the stone
5.3-THE MINERALOGICAL COMPOSITION:
The mineralogical composition includes; diamond,
graphite, goethite, quartz calcite and halite.
5.3.1-Diamond: Diamond aggregations occur as tiny angular grains (fragments)
showing the characteristic lustre and cleavage. Some of these grains show
indications of octahedral form), but others are suggestive of partial hexagonal
form. EDAX analysis (Fig. 5.3) of some grains indicates that they consist
essentially of C (~98 %).
The XRD analysis data are consistent with the presence of diamond of interplanar
distances (d) 2.07, 1.259, and 1.881 (JCPDS, card 6-675) as indicated by the
Camera method. Moreover, diamond appears through the chart of the other X-ray
Raman spectrometric analysis of the bright aggregates confirms the presence
of diamond in a polycrystalline status, as witnessed by the significantly
broad peak at 1331 cm-1, spectra b and d). In spectrum (b), diamond is associated
with graphite (peak in the 1580 cm-1 region). In spectrum (d), the broad band
at 1332 cm-1 is a good evidence for the presence of diamond in the form of
microcrystalline aggregates (note the sharp peak of the well crystalline diamond
on the reference spectrum c). Thus, the observed large grains represent quite
large aggregates of micrometer-sized crystallites.
5.3.2-Graphite: Graphite occurs as thin laminated encrustation coating and
embedding the diamond aggregations. The Raman spectroscopy confirms also the
intimate association between graphite and diamond (Fig. 5.5, spectrum b).
Graphite is also present in the form of microcrystalline grains. In figure
(5.5, spectrum a) the single peak at 1580 cm-1 is of crystalline graphite
(mean basal plane >>1000 Ĺ). This phase is also known as the G mode. Progressive
disorder in graphite is reflected in the Raman spectrum by the broadening
and shifting of this band to higher wave numbers, and by development of an
additional band near 1360 cm-1 (also known as the D mode) (Pasteris and Wopenka,
1991; Hirlimann, et al., 1992). The peak around 1360 cm-1 in spectrum b (Fig.
5.5) is aconvolution of two peaks. This is due to the presence of both diamond
and graphite in intimate association.
Probably the first detected
Kimberlite pipe nearby the Silica strewnfield
This piece from the
breccia contain large dark brown diamonds
a trekking-tour in 2013
DISCOVERY OF Fe-Cr-Ni SPECKS WITHIN QARET EL-HANASH
BRECCIA OF THE LIBYAN GLASS AREA SOUTH WESTERN EGYPT
A. El-Kammar, I. Arafa, K. A. Soliman & A. Barakat --7th International
Conference on the Geology of the Arab World, Cairo University, Feb. 2004,
The rock consists of various fragments of local sandstone,
i.e., from the area of the glass distribution itself. Fragments of igneous
source have never been recorded. The rock fragments range from fraction
of mm up to 4-cm in diameter, in the collected specimens. The rock fragments
vary in colour from creamy white to brownish-red. They are angular to
subrounded and embedded in a dull greyish-black matrix. The microscopic
investigation and scanning electron microanalysis confirmed the above-mentioned
observation and showed that the matrix consists of shattered and fragmented
quartz grains of various sizes. In addition to quartz, the matrix contains
many other phases, such as glass, zircon, clay minerals, wollastonite,
ilmenite, Mg-ilmenite, rutile and Fe-Cr-Ni specks.
There are several metallic specks of various sizes ranging from 1 micron
up to about 10 micron, dispersed in the matrix of Qaret el Hanash breccia.
They invade some of the quartz grains. These specks are mainly of irregular
outlines and some of them show clear fissures. They are associated with
glass and intercalated in some cases with halite. EDAX analyses of such
specks indicate that they consist of native Fe, Cr and Ni, in addition
to subordinate Si and Ca. Finer particles of similar appearance have also
been noticed by the petrographical microscope through the fractures of
some of the quartz grains.
The most interesting achievement of the chemical analyses is the detection
of high Ir content (2.0-2.2 ppb) within the breccias. This value represents
the highest reported values for the area. The reported value of Ir in
other breccias in the area is around 1.6-1.9 ppb. The highest reported
concentration of Ir by the previous studies was detected from the black
streak portions from the Libyan glass itself is 1.25 ppb.
Aly Barakat on May 19, 2018: The samples contains tiny
particles of Fe-Cr-Ni, and other phases includes tiny grains of
moissanite and diamond.
Aly Barakat, 2004: At latitude
25°22′51″ N and longitude 25°27′34″ E is present site of a megascopic
breccia. The petrographical and mineralogical studies carried out on the
breccia indicate that it represents impact breccia. In addition
to the brecciation of the quartz grains some of these grains show PFs
and PDFs. The zircon of this breccia shows evidence of deformation as
represented by the fragmented nature of some the studied grains and by
non-stoichiometric contents of ZrO2 and SiO2. The detection of
glass and graphite is accounted also
for the impact origin of this breccia.
5. Debris in Paleosol
Polymetallic and carbonaceous debris in paleosol from the
Libyan Desert Glass strewn field, SW Egypt: Evidence of a cometary impact.
M. A. G. Andreoli, & M. Di Martino et al. -- Lunar and Planetary
Science XLVIII (2017),
An expedition in November 2011 to the find area of "Hypatia" failed to recover
additional hand specimens of "Hypatia" material, but samples of pedogenic
(Cenozoic) pebbly deposits. One of these samples was collected 3.8 km SSW
of the Hypatia sampling site.
After fractional separations of the sample was identified evidence of
hard amorphous carbon and submicron diamonds
as well as unusual metallic mineral grains, all those found in the "Hypatia"
The unusual metallic grains and carbonaceous particles tentatively grouped
into 4 types
Type I grains and spherules range from 10-20 μm up to 130 μm. SEM-EDX
data indicate that the smaller spherules are metallic with a wide compositional
range comprising Ti, Ag, Al, and Si in varying porportions, and Ca, O, Na,
Mg and S as variable, minor constituents. The largest spherules are pale green
and vitreous and consist entirely of P, Si with no detectable oxygen.
Type II grains are much larger (length: 60 μm to 1.2 mm) and consist
a) sintered aggregates of Pb metal particles
b) strongly sintered clusters of α-Ti (+1.0 at.% Al) subgrains
c) more brittle aggregates of seemingly submicron, Sn-Ca alloy particles.
The Ti metal grains in places host clusters of quenched gas bubbles, blobs
of Ti aluminide, veinlets of non-stoichiometric Ti nitride, Al oxycarbonitride,
and particles of Zr, Ag, and Zn. A distinctive feature of the Type II grains
is their localized coating by (C, O bearing) carbonaceous films and filaments
up to 300 μm in length. Although these resemble fungal hyphae and tendrils
in SEM images, Raman spectra prove that they comprise partly graphitized kerogen.
Type III grains are shard-like in shape and occur either as partly
oxidized branching (70 μm x 50 μm) Al particles decorated by μm-size Bi granules,
or as lace-textured Ti particles partly enveloped by Type II grains. Petrographic
textural analysis of multiple 3-D sections of the shard indicate that the
Type II (and perhaps Type I) grains were derived from the partial to complete
melting of the Type III shards.
Type IV grains are morphologically and compositionally diverse, with
common characteristics being Carbon as the major constituent. Moissanite (SiC)
grains were the first to be positively identified from petrography and Raman
spectra. Other grains display a range of textures, including one resembling
a honeycomb with N as second major constituent and minor, varying amounts
of S and Cl. The Raman spectra of these N-rich grains show faint, indistinct
D and G bands but distinctive peaks in the 3000 cm-1 region, indicative of
6. Mullite-magnetite-glass melt rock
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 (left); 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 southeast of the
7. Crater Zerzura
|Cigolini & Di Martino --
Here a spectacular find of a breccia from a crater-like structure
is presented, in which probably a swarm
of micro-diamonds can be seen.
Unfortunately, apart from the identified location of the find (25°16'46
"/ 25°10'05") there are no further comments. The crater is
in the Wadi Zerzura, which is located west of the Silica strewnfield.
The crater is nearly round and in no case a depression caused by water
erosion. In the crater's center there is at least one round hole with
a plug of the breccias.
The breccia in the crater may be a kimberlitic emplacement in the
decomposition phase. The diamonds (white "sugar") are difficult to
recognize in the photos.
But some forms seem to be transparent crystals.
Romano Serra, University of Bologna, has sent me some
new revealing photos from the crater and the breccia. It were only made
30 thin sections to find PDF's.