Chemistry or geology, chemistry or geology… I went back and forth on this so many times in my final year of high school (the now defunct Grade 13). And then I found geochemistry – problem solved. But so many elements, so much choice. Here, I am going to regale you with tales of one of my very favorite elements: vanadium.  It is a fantastic little transition metal with oxidation states aplenty and a couple stable isotopes too. Its pesky chemistry made it particularly resistant to early attempts at uncovering its isotopic composition, but since that challenge was solved in 2011, the isotopic composition of vanadium has been applied to challenges in fields spanning cosmochemistry, to magma genesis, to oceanography, to biology. There is, however, still so much to learn.  I’ll focus on three themes: (1) magmatic processes and the tantalising links to mineral deposit genesis, (2) chemical oceanography, using an example of what we hope to learn via an upcoming expedition to the Beaufort Sea in the Canadian Arctic and (3) a bit of techno-geek-speak on the wonderful world of vanadium isotope measurement. Right now, there is no lab in Canada able to measure vanadium isotopes.  All that will change in January 2027, with installation of a shiny new instrument here at EOAS that can measure precise vanadium isotope signatures using an order of magnitude less vanadium than our standard methods.  Imagine, instead of 1000mL of seawater, we now need only 100mL…instead of a ‘whole rock’, we now can measure a single grain or a mineral zone. So, please join me for 45 minutes of pure vanadium fun.