NIOBIAN CESSTIBTANTITE FROM THE DOBRA-VODA LEPIDOLITE PEGMATITE, WESTERN MORAVIA, CZECH-REPUBLIC

Cesstibtantite is a very rare member of hydrothermal alteration minera l assemblage replacing primary stibiotantalite from lepidolite pegmati te at Dobra Voda near Velke Mezirici, western Moravia, Czech Republic. Microlite, its antimonian and strontian varieties and stibiomicrolite predominate over later manganotantalite and ferrotapiolite in this as semblage. The Nb,Ta-oxide minerals are characterized by Ta/(Ta+Nb)at. = 0.78-0.67, maintained throughout primary to secondary crystallizatio n. Niobian cesstibtantite exhibits Ta/(Ta+Nb)at. = 0.75-0.71, (except one spot with 0.57). As a stable Nb/Ta ratio seems to be common in lat e hydrothermal alteration parageneses after stibiotantalite, a discove ry of Nb-analogue of cesstibtantite may be expected at localities of s tibiocolumbite.