agreed. these minerals both have One Cool Trick that had me rooting for them over the course of the Cup (kyanite's anisotropic hardness, tugtupite's color change). both very good.

I'm voting kyanite because I think if it doesn't win this year it doesn't ever win, but it's tugtupite's first year.

Dioptase‘s color is like one of those magical deep swimming holes you dive into from a high rock. I just can’t get excited by tugtupite’s pink. Vote dioptase! #MinCup25

#MinCup25 Quarterfinal 2: It's #perovskite and its intriguing structure against #tugtupite's collection of optical tricks for this quarterfinal match!

Vote: www.mineralcup.org/2025/vote/r3...
Results: www.mineralcup.org/2025/results...

Caesium-rich pollucite is mined for use in oil drilling. Tugtupite’s name comes from Inuit for reindeer blood. It’s vitreous, transparent to translucent, tenebrescent (changes colour in UV). Called the “King of Fluorescent Minerals,” is phosphorescent so gets my physics vote plus a gem. #MinCup25

Oh dear. What you’ve written fits all too readily into the song “Plastic Jesus.”

Tenebrescent & fluorescent
In UV, and phosphorescent,
A Greenlander that changes with the times.
Bright in summer, dim in winter,
It needs your vote to be a winner.
Tugtupite’s a name to know and love!