
Chiappinoite-(Y) Field of view: 0.6 mm Locality: Pumice quarry, Ribeira Grande, São Miguel, Azores, Portugal ( locality at mindat.org ) — Photo: Henk Smeets – tomeikminerals.com · CC BY 4.0
Chiappinoite-(Y)
Chiappinoite-(Y) is an IMA-recognized mineral species in the silicate class, with the chemical formula Y₂Mn(Si₃O₇)₄.
It crystallizes in the orthorhombic crystal system (space group Ibam).
Key properties: Mohs hardness 6; specific gravity 3.09; White streak; Vitreous luster; optically biaxial.
IMA symbol Cap-Y, IMA status: approved, named in 2014.
Found in vugs in a block of peralkaline syenitic volcanic ejectum.
It is found associated with Astrophyllite, dalyite, elpidite, fluornatropyrochlore, kentbrooksite, albite, quartz, aegirine.
The mineral was named to honor Luigi Chiappino (b. 1950), a distinguished mineral collector of Milan, Italy, who discovered the first specimen.