Environment: Banded skarns and recrystallized limestones. Original magnesiosadanagaite (IMA1982-102) was ranamed potassic-magnesiosadanagaite by IMA amphibole nomenclature committee.
Locality: Myojin Island, Ehime Prefecture, Japan. Link to MinDat.org Location Data.
Optical Data: Biaxial (-), a=1.674, b=1.686, g=1.699, bire=0.0250, 2V(Calc)=90, 2V(Meas)=90.
Pleochroism (x): colorless or pale brown.
Pleochroism (z): brownish yellow or greenish brown.
note: Specific Gravity of Potassic-magnesiosadanagaite =3.27 gm/cc.
U=PEPotassic-magnesiosadanagaite x relectron= 17.79 barns/cc.