Rosette-shaped sewardite aggregate (PXRD- and EDS-analysed). SEM micrograph.
Deep-red rounded to rosette-shaped sewardite aggregates (PXRD- and EDS-analysed), with a diameter of about 0.1 mm. The sewardite is associated with fine-grained, yellowish beudantite/segnitite (slightly K- and Cu-bearing).
The sample was originally in the collection of the Smithsonian ("arsenobismite"; catalogue # 104010) and kindly provided on loan by curator Dr. Jeffrey Post.