Blogging a crystal structure a day in 2014


Contributed by

Helen Maynard-Casely

Mineral in pink – Spherocobaltite

What does it look like?

Two views of the Spherocobaltite structure, blue atoms are cobalt, red oxygen and brown are carbon.

Two views of the Spherocobaltite structure. Blue atoms are cobalt, red oxygen and brown are carbon.

What is it?

When you think of the word 'mineral' and then imagine the types of colours that associate with that – you've probably got 'grey' or 'rock-coloured' in your head first? I hope that on this blog so far we've managed to show that minerals can really come in all colours – through the 'magic' of chemistry.

"Spherocobaltite-260478" by Rob Lavinsky / iRocks.com Licensed under CC BY-SA 3.0 via Wikimedia Commons.

Today's is pink! Spherocobaltite is colbate carbonate (or CoCO3), and it's the cobalt that gives this mineral its lovely pink hue. It's a hydrothermal mineral, forming originally from a hot soup of elements.  It's usually found in veins, where the hot fluid has flowed through crack in the rock.

It you think you have seen this all before, then you've obviously been pretty keen on our blog! The structure of spherocobaltite is the same as calcite (CaCO3), only with cobalt atoms instead of calcium ones.

Where did the structure come from?

The structure of Spherocobaltite that we've featured was determined by Graf in 1961 and was published in the journal American Mineralogist. It's #9000101 in the Crystallography Open Database.

Tags: colours   mineral   pink