AM_Howlite Formula: Ca2 Si B5 O14 H5 Name: Howlite Unit cell: 12.78 9.33 8.6 90.0 104.83 90.0 , V=991.28 Space group: P121/C1 (14)

Finney J J , Kumbasar I , Konnert J A , Clark J R , American Mineralogist , 55 (1970) p.716-728, Crystal structure of the calcium silicoborate, howlite