Home > Western U.S. – August 22 > MS1242 Luinaite-(OH)

Luinaite-(OH) - Sold

Bald Hornet claim
North Bend
King County
Washington
U.S.A.

3.0 by 1.9 by 1.1 cm – Thumbnail specimen (fits into a 2.5 cm cube)

Luinaite-(OH) is a tourmaline group mineral, specifically the first monoclinic tourmaline species. Cation ordering causes a lowering of the ideal hexagonal symmetry. The end member composition is NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄; dimorphous with schorl. This material comes from one of the localities listed in the 2009 IMA approval list. Bart Cannon, a mineral collector based in Seattle, collected these specimens in the 1970s. Single crystal X-ray diffraction of this material at the University of Arizona clearly demonstrate the monoclinic symmetry. Download the X-ray data here. Also find qualitative chemical data here. This is a fine example with crystal sprays to 2.3 by 1.4 cm and lustrous quartz crystals for contrast. This is a large piece for the find. A good thumbnail for rarity points.