M. Franzini et N. Perchiazzi, PORTITE DISCREDITED = NATROLITE AND NEW DATA ON SCHNEIDERITE (= LAUMONTITE), European journal of mineralogy, 6(3), 1994, pp. 351-353
The sample of portite studied by D'Achiardi (1873), a fragment of the
holotype of Meneghini & Bechi (1852), was rediscovered in some of the
oldest collections of the Natural History Museum of Pisa University. X
-ray and optical data demonstrate that portite is identical to natroli
te, thus allowing us to discredit the mineral name portite. This propo
sal is approved by the I.M.A, Commission on New Minerals and Mineral N
ames. Moreover, X-ray data show ''schneiderite'' to be identical to la
umontite.