Epic #kyanite crystals reveal their colors when split open. We are tracking variation in extent of kyanite to sillimanite transformation in a metamorphic dome — it varies from 0-100% with structural location in the dome: one of the many geo-useful and fun things you can do with kyanite. #MinCup25

These white #kyanite crystals in a biotite-gedrite schist from central Australia somehow missed out on the titanium, iron, and other trace elements that kyanite typically contains to give it the iconic blue and other colors. #MinCup25

This rock in western Norway originated as basalt in an ancient ocean, then it was buried (subducted) tens of kilometers and heated over 800 C to create this beautiful #kyanite. The alignment of the kyanite indicates deformation. #MinCup25

Chromium-rich #kyanite blood, as seen with cathodoluminescence imaging. #MinCup25

#kyanite party (Roan, Norway) #MinCup25

I’m very excited that #tugtupite made it to the finals but can it do this? Folded #kyanite in a high-pressure quartzite, western Türkiye. #MinCup25

Hematite is red, #kyanite is blue, And also green, white, black, and orange too #MinCup25

#kyanite (blue) replacing or being replaced by pink #andalusite. Bonus: there is also #sillimanite, so this a rare locality containing 3 Al2SiO5 minerals (polymorphs). Lesjaverk, Norway. #MinCup25

#kyanite wave (Western Gneiss Region, Norway) #MinCup25

NOTE: MSA Inaugural Annual Meeting: Feb, 16-18, 2026, Tucson, AZ, USA This will follow the Tucson Gem and Mineral Show. On Feb. 17 and 18 there will be a series of talks and poster sessions. Abstracts due: Oct. 31. Registration will be through the MSA website at www.msaweb.org

#kyanite fields forever, or until the next orogeny #MinCup25

#kyanite in biotite gneiss from the Entia Dome, central Australia. Kyanite forms deep in the crust before it makes its way to the Earth’s surface, a slow and much more challenging journey than taenite’s fall through space. #MinCup25

#kyanite volcano (not really a thing but a nice way to display the different colors of kyanite) #MinCup25

#Garnet swimming in a sea of #Titanite in a Franciscan Complex metamorphic rock, as seen in plane and cross polarized light. Photo by Sarah Brandt. #MinCup25

#Titanite from the Franciscan subduction complex, California, as seen under plane and cross polarized light in a petrographic microscope. Field of view about 2 mm. Photo by Sarah Brandt. #MinCup25

Magnetic and Crystallographic Fabric Analyses of Amphibolite: A Proposed Methodology Applied to a Migmatite Dome - Hamelin - 2025 - Journal of Geophysical Research: Solid Earth - Wiley Online Library agupubs.onlinelibrary.wiley.com/doi/10.1029/...

#kyanite is beautiful at all scales, #MinCup24

Pink #corundum with green #clinopyroxene in thin section (plane light, 2 mm FOV), Berit metaophiolite, Türkiye, #MinCup24

#corundum in a petrographic thin section (plane light), with green #clinopyroxene, field of view ~2 mm, Doğanşehir, Türkiye, #MinCup24

#Titanite from gneiss from Finnøya, Norway, as seen in thin section. Clear, rounded inclusions are apatite. Field of view ~0.5 mm. #MinCup24

#Kyanite in blue, green, white, and black. #MinCup24

A heap of #quartz. Go ahead and try this with mercury. #MinCup24

#omphacite #MinCup24