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Imaggeo On Monday: Geometric Microscape of Agate

Bernardo Cesare January 3, 2022

Geometric Microscape of Agate . Credit: Bernardo Cesare (distributed via imaggeo.egu.eu)

“Crazy Lace” is an agate collected in Mexico, which offers great opportunities for aesthetic photomicrography. Here we see the common arrangement of fibers of chalcedony (microcrystalline quartz) in parallel bands alternating with black thin layers of Fe oxides. Polarized light photomicrograph, crossed polarizers and red tint plate. width 5.4 mm. Sample kindly provided by Denise M. Har ...[Read More]

Imaggeo On Monday: Blue Olivine in an unusual basalt

Bernardo Cesare September 28, 2020

Blue Olivine in an unusual basalt. Credit: Bernardo Cesare (distributed via imaggeo.egu.eu)

Blue Olivine set in a matrix of pyroxene, magnetite and plagioclase in a basalt collected by the photographer, Bernardo Cesare, on the shore of the Sea of Galilee, Israel. Polarized light photomicrograph. Crossed polarizers and red tint plate. Width c. 2.7 mm. Who may have been throwing this stone a couple millennia ago? Description by Bernardo Cesare, after the description on imaggeo.egu.e ...[Read More]

Colour deficient vision and the geosciences; just another way of looking at things

Simon Jowitt September 18, 2020

Mineralogically complex drillcore from Australia (Photo by Simon Jowitt)

Like a reasonably large proportion of the population, I have colour vision deficiency (also known as colour deficient vision or colourblindness). I’m not going to get into the technical aspects of what this is like as they are covered well here and here, and you can do an Ishihara test, and other tests here, to check your own vision. The other reason I’m not going to discuss the technicalities of ...[Read More]

Imaggeo On Monday: Emoji from meteorites; impact spherule

Seda Özdemir September 14, 2020

Emoji from meteorites; impact spherule. Credit: Seda Özdemir (distributed via imaggeo.egu.eu)

This is a crossed polarized light photomicrograph of an impact spherule; a small mineralisation made when a meteorite hits the Earth and melts the rock at the point of impact, from Barberton Greenstone Belt, in South Africa. These spherules are the only remnants of Early Earth’s meteorite impact history, from between of 3.2 and 3.5 billion years ago. In this photo you can see the K-feldspar ...[Read More]