Willemseita: Silicate hydroxylated of nickel with molecular structure of phyllosilicate sheets of mica, composed of rings of tetrahedrons and octahedrons, with impurities of magnesium, aluminium, iron, cobalt, calcium and water, which crystallizes in the monoclinic system and prismatic.
* Only one "like" per meaning and day, the more "likes" the meaning will appear higher in the list