EGU Blogs

Photo of the Week

Photo of the Week

Keepin’ then comin’! This weeks photo is brought to you by Immageo as per usual. It can be found: here

The image was taken by Dmitry Tonkacheev, IGEM RAS, Moscow, Russian Federation.

Dmitry writes, “This is Co-bearing sphalerite, synthesised using gas transport method at 850C looks like the Christmas Tree. Although presented intergrowth of crystals was made in the laboratory, there are some natural samples, that comes from Africa. Green sphalerite from Congo can be used as jewellery.”

I have to chip in that incorporating Co into minerals can often lead to some very unsusual colours. For example, cobaltoan calcite is brilliant, neon pink.

Quartz over Malachite on Cobaltian Calcite

Cobaltoan Calcite from Katanga, Congo. (Source)

Matt Herod is a Ph.D Candidate in the Department of Earth Sciences at the University of Ottawa in Ontario, Canada. His research focuses on the geochemistry of iodine and the radioactive isotope iodine-129. His work involves characterizing the cycle and sources of 129I in the Canadian Arctic and applying this to long term radioactive waste disposal and the effect of Fukushima fallout. His project includes field work and lab work at the André E. Lalonde 3MV AMS Laboratory. Matt blogs about any topic in geology that interests him, and attempts to make these topics understandable to everyone. Tweets as @GeoHerod.