Keywords: Calcite Nb Medford.jpg Calcite containing Niobium giving it distinctive bluish color from Medford Quarry Caroll County Maryland Collected 2002 Scale bar is 1 cm 2010-2-6 Own <br />Transferred from http //en wikipedia org en wikipedia Jstuby at http //en wikipedia org en wikipedia en wikipedia Jstuby Original upload log page en wikipedia Calcite_Nb_Medford jpg 2010-02-06 19 12 Jstuby 458×486 53085 bytes <nowiki>Calcite containing Niobium giving it distinctive bluish color from Medford Quarry Caroll County Maryland Collected 2002 Scale bar is 1 cm </nowiki> Calcite |