Canon EOS 5D Mark IV
ƒ/2.8
65 mm
1/200
6400
From the unusual Gujba bencubbinite full of metal blebs. Made in space.
3 responses to “Meteorite Gujba Grains at 2x Zoom”
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A good writeup on Gujba: "It is generally assumed that a protoplanetary impact gave rise to a vapor cloud with high enough partial pressures to generate a metal-enriched gas. The metal globules then condensed as liquids from this gas and were sorted by size and density, thereby establishing the high metal/silicate ratio of the group.
Through 3-D mapping of Gujba at a micrometer scale, at least five types of metal particles of differing Ni content (~5 to ~8.2 wt%) and sulfide content were identified. These metal particles are consistent with an origin in an impact plume, followed by accretion to a secondary parent body, where they experienced impact-associated secondary heating. The metal globules have varying Ni contents and exhibit quench textures. Due to the fact that no diffusion has occurred among globules in contact with each other, it can be inferred that they were accreted at cold temperatures after being isolated from the hot condensation region.
Shock-associated structures identified in Gujba include stishovite, amorphous to poorly graphitized carbon, ordered graphite, rounded to euhedral diamonds, nanodiamond clumps, and rare bucky-diamonds, along with carbonaceous nanoglobules."
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and from Laurence Garvie, reacting to these photos: "For me, the interesting materials are the shocked phases in the matrix between the metal and large silicates. We discovered interstratified graphite diamond (which we called diaphite 1), stishovite and an unidentified high pressure Al silicate in this matrix material. There are many more interesting phases in the Gujba matrix waiting to be described."
and zooming out to 
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