Disthen (Kyanit) - Arzo ridge, Robiei, Val Bavona, Ticino, Switzerland
 
Elongate flattened Disthene crystals up to 6.5 cm in length, partly with thin dark blue colour stripe and marginal transformation into silvery mica, embedded in glassy vein quartz with Böhm-type striation. Unusual formation in the hanging quartz vein of the large Clinochlore fissure No.201 on the Arzo ridge. This new find in September 2020 yielded the best Disthene specimens of the entire region between Cavagnoli and Val Sambuco!