CHEMICAL AND MINERALOGICAL ASPECTS OF SCAPOLITES OF ARACRUZ AND NOVA VENÉCIA – ES
Chemical and mineralogical aspects of scapolites from Aracruz and Nova Venécia - ES
DOI:
https://doi.org/10.5016/geociencias.v41i1.16414Abstract
The scapolite consists an isomorphic-series of aluminosilicates minerals, involving the end members Marialite (Ma) - Na4Al3Si9O24Cl and Meionite (Me) - Ca4Al6Si6O24CO3, as gem minerals varieties. In the state of Espírito Santo, it was recorded occurrences of yellowish prismatic scapolites with good transparency. The presented study aims to scapolites characterize from Aracruz and Nova Venécia – ES, understand a mineralogical and chemical aspects, using techniques as XRD, SEM-EDS, SEM-CL, optic-CL and Electron Microprobe (EPMA). The compositional studies through of EPMA and semiquantitative analyses of SEM, allowed to trace compositional correlations and characterize the scapolites of deposits as calcium-marialite (Me19-Me40). The XRD analyses allowed correlate a presence of Cl and changes structures, between samples of deposities. The spectral of CL revealed orange luminescence at 600-602nm and red at 645nm, with different intensities between deposits. The chemical profiles identified a S-2 ion as luminescence activator element in the scapolites.
Keywords: Calcium-marialite; Gem-mineral; Mineral chemistry; Mineralogical characterization