Original paper
Strontiopiemontite, a new member of the epidote group, from Val Graveglia, Liguria, Italy
Bonazzi, Paola; Menchetti, Silvio; Palenzona, Andrea
European Journal of Mineralogy Volume 2 Number 4 (1990), p. 519 - 524
9 references
published: Aug 21, 1990
manuscript accepted: Mar 20, 1990
manuscript received: Nov 29, 1989
DOI: 10.1127/ejm/2/4/0519
Abstract
Abstract Strontiopiemontite, a new member of the epidote group with simplified formula CaSr(Al, Mn, Fe)3- Si3O11O(OH), occurs as small deep red prismatic crystals in the manganese ore deposit of Val Graveglia, Liguria, Italy. Physical properties, including the powder pattern, are similar to those of piemontite. Crystals are often twinned {100}. Crystal structure refinements performed on two separate crystals clearly show that the entry of Sr into the structure mainly occurs on the A(2) site (max. 70%) and leads to a significant increase of the A(2) polyhedron volume as well as the c • sinβ value.
Keywords
Strontiopiemontite • epidote group • structure refinement • chemical analysis