One of the great privileges of studying geology at university is spending time looking at thin sections. It may not feel like it at the time – learning to identify minerals down the microscope is hard work – but peering into the secrets of the earth is deeply satisfying, both intellectually and aesthetically.

Lovely oscillatory zoning in a titanaugite rimmed with aegrine. sanidine and nepheline in the gm #thinsectionthursday pic.twitter.com/Mck2iwzGhH — Chris Jennings (@chrsphr) May 1, 2014

For those of us who don’t have access to the kit (thin slices of rock, specialised microscopes) we have to make do with photographs. So I was very pleased to discover that rock-whisperer Chris Jennings (@chrsphr) has invented the Twitter hashtag #thinsectionThursday.

Can we make #thinsectionthursday a thing? Olivine basalt from Rum, XPL. pic.twitter.com/lpWgz2W3XY — Chris Jennings (@chrsphr) May 1, 2014

Twitter is a great place to share images, and Earth Scientists have long made use of this, posting pictures of long-dead animals (#fossilFriday) and dangerous piles of clinker (#volcanoMonday) on particular days. The potential of #thinsectionThursday is enormous. Thinsection images are often visually stunning – with varied colours and textures – plus the educational potential is vast. They can show crystals that grew in the heart of a volcano, a detailed cross-section of a fossil or the jumbled joyful chaos of a metamorphic rock. Archaeologists, meteorologists and others can play too.

Here's one for #thinsectionthursday. Quartzofelspathic mylonite being squeezed around a garnet porphyroclast pic.twitter.com/pouuRwg7X5 — Andrew Cross (@TectonoAndy) May 1, 2014

I’ll be contributing to #thinsectionThursday, please do join me. If you use thin sections day to day, it’s a no-brainer: take pictures from your course-work or research and get tweeting. If you’re not on Twitter, you can still view the images. If you don’t have your own photos, there are other options….

If you use other peoples images on Twitter, you’re benefiting from their hard work, so it is very important to use proper attribution. Lot’s of famous accounts don’t bother, but you are better than them, aren’t you?

One resource I’ve made use of is the British Geological Survey. They have digitised thousands of thin section images as part of their GeoScenic image database *and* within their rock collections (search for S% in the registration number field). They are available for non-commerical use, provided you say it’s their image and provide a link back. It’s always good manners to ask, of course, but I’ve done this on your behalf:

@metageologist This is great, that credit is ideal, thanks for sharing our images! Carry on the great work — BGS (@BritGeoSurvey) May 3, 2014

So, what are you waiting for?

…

Thursday, obviously.

And the opportunity to make #thinsectionThursday the success it deserves to be.