Granite pegmatite.
Note on the mineral list: the "thalénite-(Y)" from here was recently found to be fluorthalénite-(Y) (Raade & Kristiansen).
References:
- Vogt, Th. (1922): Über Thalenit von Hundholmen im nördlichen Norwegen. in Brøgger, W.C, Vogt, Th. & Schetelig, J. (1922): Die Mineralien der südnorwegischen Granitpegmatitgänge. II. Silikate der seltenen Erde. Videnskapsselskapets Skrifter. I.Mat-Naturv. Klasse 1922. 11, 19-47 + plates VII-IX.
- Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 276.
- Nilssen,B. (1973): Gadolinite from Hundholmen, Tysfjord, North Norway. Contribution to the mineralogy of Norway no 55. Norsk Geologisk Tidsskrift, 53, 343-348.
- Eldjarn, K. (1978): Ancylitt fra Hundholmen, Tysfjord. NAGS-nytt 5(3), 18 (in Norwegian).
- Eldjarn, K. (1988). Etter Neumann. NAGS-nytt 15 (1-4), 62 (in Norwegian) [on boltwoodite].
- Kristiansen, Roy (1993): Thalenitt fra Hundholmen, Tysfjord. STEIN 20 (2), 121-123.
- Husdal, T. (2008): The minerals of the pegmatites within the Tysfjord granite, northern Norway. Norsk Bergverksmuseum, skrift 38, 5-28.
- Raade, G. & Kristiansen, R. (2009): Fluorthalénite-(Y) from Hundholmen, Tysfjord, north Norway. Norsk Bergverksmuseum, skrift 41, 21-24.
