O seladonicie z Barczy w Górach Świętokrzyskich
Abstract
CELADONITE FROM BARCZA IN THE ŚWIĘTY KRZYŻ MOUNTAINSCeladonite occurs as chief component of Lower Devonian (Emsian) tuffite appearing within the sandstones of the Barcza beds. lt forms 70 to 90% of the tuffite mass, occurring in the shape of submicroscopic plates the largest of which attains 0.02 mm. in their direction of elongation. Less frequently has celadonite been reported, in the shape. of spherulites, of 0.08-0.45 mm. diameter (Plate 1, Figs. 3, 4). Pleochroism of individual plates is almost unnoticeable, but aggregated deposits show in the Nγ direction a yellowish-green colour, whereas in the remaining directions they are yellowish or colourless. The investigated celadonite is uniaxial, or discloses an angle of optical axes 2Vα = 5°; it is optically negative. Measured in immersion fluid, the refractive index in direction Nγ is in some prisms = 1.579, in others = 1.581.Downloads
Issue
Section
Articles
License
Authors who publish with this journal agree to the following terms:- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as this can lead to productive exchanges and earlier and more frequent citation of the published work (See The Effect of Open Access).