Mineralpedia Details for Penkvilksite
Named after the Lapp words used to describe its usual appearance: penk, meaning “curly,” and vilkis, meaning “white.” Penkvilkisite can be found only in the Jubilee pegmatite in the Lovozero massif in the Kola Peninsula, Russia, and at Mont Saint-Hilaire in Quebec, Canada. At the type locality in the Jubilee pegmatite, Penkvilksite occurs in the natrolite zone of the pegmatite, and at Mont Saint-Hilaire it occurs in a pegmatite vein cutting a marble xenolith.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/penkvilksite.pdf
Penkvilksite from Yubileinaya peg., Karnasurt Mt., Lovozero Massif, Kola Pen., Russia
Textbook "cauliflower-like accumulations" or dull porclein, rounded or ball-like aggregate to 9mm set nicely in a pink Zorite(?) matrix. The book (Lovozero Massif, highly recommended by the great Russian mineralogist Igor Pekov) also describes it as snow white, matted aggregates.