Whelanite

IMA formula: Cu₂Ca₆[Si₆O₁₇(OH)](CO₃)(OH)₃(H₂O)₂

Crystallography: Orthorhombic. Pn2n. a = 5.6551(4) Å, b = 3.683(3) Å, c = 27.1372(7) Å. Z = 1.

Specimen #18. Whelanite (blue), tobermorite (white fibers), and grossular (yellow). Christmas Mine, Christmas, Banner Mining District, Gila County, Arizona, USA. FOV 5.3 mm.