Weloganite

Weloganite is a rare carbonate mineral with formula: Na2(Sr,Ca)3Zr(CO3)6·3H2O. It occurs in an igneous carbonatite sill in Montreal, Canada in the Francon Quarry where it was first discovered. It also occurs in the Mont Saint-Hilaire district. It is usually white, lemon yellow, or amber in color, and can be translucent. It crystallizes in the triclinic system and shows pseudo-hexagonal crystal forms. It was named for Canadian geologist Sir William Edmond Logan (1798-1875).
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General Information:
 Chemical Formula:
Sr3Na2Zr(CO3)6·3(H2O)
 Composition:
(Molecular Weight = 814.16 gm)
Sodium 5.65 % Na
Strontium 32.29 % Sr
Zirconium 11.20 % Zr
Hydrogen 0.74 % H 
Carbon 8.85 % C 
Oxygen 41.27 % O 
 Empirical Formula:
Sr3Na2Zr(CO3)6·3(H2O)
 IMA Status:
Approved IMA 1968
Physical Properties:
 Cleavage:
[0001] Perfect
 Color:
white, lemon yellow, amber, or colorless.
 Density:
3.22
 Diaphaniety:
Transparent to Translucent
 Hardness:
3.5 - Copper Penny
 Luster:
Vitreous (Glassy)
 Streak:
white
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