General Information:
Chemical Formula:
(Ba,K,Pb)Na3(Ca,Sr)(Fe++,Mg,Mn)14Al(OH)2(PO4)12
Environment:
In a phengitic quartzite.
IMA Status:
Approved IMA (Dana # Added)
Locality:
Near Madesimo, Spluga Valley, Central Alps, Italy.
Name Origin:
For Pietro Sigismund (1874-1962), a well known collector of minerals from Valtellina, especially Val Malenco.
Physical Properties:
Cleavage:
[???] Perfect
Color:
grayish green.
Density:
3.54
Diaphaniety:
Translucent
Habits:
Aggregates - Made of numerous individual crystals or clusters., ,
Luminescence:
Non-fluorescent.
Luster:
Greasy (Oily)
Streak:
white
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