FMF Minerals Gallery

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Nepheline (?), Aegirine
Ilímaussaq Intrusive Complex, Narsaq, Greenland
FoV: 5 x 4 cm
(side view of the piece on the previous photo)
Formation of Nepheline shows the lack of silicium in the magma.
It can be difficult to distinguish from feldspar, as it has similar colur and hardness, but it lack clear cleavage and has a somewhat greasy lustre - I am almost sure most of the gray substance we see here is nepheline. (in other areas of the same stone there is also a bit of feldspar, see previous pic) (Author: kakov)