Pumpellyite
Pumpellyite is a group of closely related sorosilicate minerals: 
*pumpellyite-(Mg): 
*pumpellyite-(Fe2+): 
*pumpellyite-(Fe3+): 
*pumpellyite-(Mn2+): 
*pumpellyite-(Al): 

Pumpellyite crystallizes in the monoclinic-prismatic crystal system. It typically occurs as blue-green to olive green fibrous to lamellar masses. It is translucent and glassy with a Mohs hardness of 5.5 and a specific gravity of 3.2. It has refractive indices of nα=1.674–1.748, nβ=1.675–1.754 and nγ=1.688–1.764.

Pumpellyite occurs as amygdaloidal and fracture fillings in basaltic and gabbroic rocks in metamorphic terranes. It is an indicator mineral of the prehnite-pumpellyite metamorphic facies. It is associated with chlorite, epidote, quartz, calcite and prehnite. 

It was first described in 1925 for occurrences in the Calumet mine, Houghton Co., Keweenaw Peninisula, Michigan and named for United States geologist, Raphael Pumpelly (1837–1923).
Q178977
sorosilicate
Concept
Q624543
monoclinic
Concept
Q898786
crystal system
Concept
Q41472
Mohs hardness
Concept
Q11027905
specific gravity
Concept
Q174102
refractive indices
Concept
Q3848788
amygdaloidal
UNK
Q43338
basalt
Concept
Q46947
gabbro
Concept
Q380971
metamorphic
Concept
Q509037
terrane
Concept
Q3303655
prehnite-pumpellyite metamorphic facies
UNK
Q427254
chlorite
Concept
Q272844
epidote
Concept
Q43010
quartz
Concept
Q171917
calcite
Concept
Q422128
prehnite
Concept
Q5024102
Calumet mine
ORG
Q45441
Houghton Co.
LOC
Q12430
Keweenaw Peninisula
LOC
Q1166
Michigan
LOC
Q30
United States
LOC
Q520549
geologist
Concept
Q377078
Raphael Pumpelly
PER
Q782700
Pumpellyite
Concept
Q782700
Pumpellyite
Concept
Q782700
Pumpellyite
Concept
1925-01-01T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
1925
DATE
+2^^http://www.w3.org/2001/XMLSchema#decimal
2
NUMBER
+3^^http://www.w3.org/2001/XMLSchema#decimal
3
NUMBER
+2^^http://www.w3.org/2001/XMLSchema#decimal
2
NUMBER
+5.5^^http://www.w3.org/2001/XMLSchema#decimal
5.5
NUMBER
+3.2^^http://www.w3.org/2001/XMLSchema#decimal
3.2
NUMBER
+1.674^^http://www.w3.org/2001/XMLSchema#decimal
1.674
NUMBER
+1.748^^http://www.w3.org/2001/XMLSchema#decimal
1.748
NUMBER
+1.675^^http://www.w3.org/2001/XMLSchema#decimal
1.675
NUMBER
+1.754^^http://www.w3.org/2001/XMLSchema#decimal
1.754
NUMBER
+1.688^^http://www.w3.org/2001/XMLSchema#decimal
1.688
NUMBER
+1.764^^http://www.w3.org/2001/XMLSchema#decimal
1.764
NUMBER
+1837^^http://www.w3.org/2001/XMLSchema#decimal
1837
NUMBER
+1923^^http://www.w3.org/2001/XMLSchema#decimal
1923
NUMBER
crystal system
named after
instance of
crystal system
country
located in the administrative territorial entity
country
located in the administrative territorial entity
country
country
country of citizenship
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