Bavenite was first described from Baveno by Artini in 1901 as monoclinic crystals of prismatic habit in pegmatitic druses in granite and given the formula 3CaO.Al2O3.6SiO2.H2O. More recently, the mineral has been described pseudomorphous after beryl from Himalaya mine, Mesa Grande, San Diego County, California, by Schaller and Fairchild (1932) and shown to contain beryllium as an essential constituent. In 1933 X-ray determinations by Ksanda and Merwin indicated a unit cell with dimensions a 9·67, b 11·53, c 4·95Å, and showed the symmetry to be orthorhombic and referable to the space-group V1, Vh1, or C2v1. Revised crystallographic orientation and optical constants were also suggested by these authors.

The material about to be described is from two localities in Switzerland. Of fourteen specimens from a fissure in the rocks below the Muotta Nera, Piz del Laiblau, Val Nalps, Tavetschthal, Graubünden, selected by Mr. F. N. Ashcroft in 1935 and 1936 from a fairly large series stocked by Adolf Caveng of Sedrun, one (B.M. 1937,598) carries the mineral as roughly radiating aggregates of platy fibres of very pale brown colour in bulk.