Fig. 4

Zone III: a Tc-in isograd locality above Alpe Zocca (Samples 1604, 1603) (coin diameter 2.3 cm). Large acicular olivine embedded in white talc and antigorite groundmass. b Olivine-talc vein at the talc-in isograd (Alpe Zocca, scale length 14.5 cm). c Plain polarised light image of the talc-in paragenesis (Sample 1603) with an upper antigorite-rich part and a lower part consisting of mosaic textured olivine-chlorite-magnetite. d Crossed polarised light image of c. Antigorite and fine grained interstitial olivine-talc in the upper part and mosaic textured olivine with talc next to chlorite in the lower part. e Massive granular olivine-talc fels (Sample Ol20, Swiss army knife 9 × 2.5 cm). f Pseudo-spinifex textured olivine-talc rock containing acicular olivine grains embedded in a white talc groundmass (Sample Ol16, Euro coin 2.3 cm in diameter). g Crossed polarised light image of granular olivine-talc fels containing chlorite, tremolite and Cr-magnetite (Ol20). h Crossed polarised light image of a pseudo-spinifex textured olivine-talc rock containing acicular olivine, fine grained talc and Cr-magnetite (Sample Ol16)