New data on yukonite

Abstract

A new occurrence of the poorly characterized mineral, yukonite, ( Ca 6.44 K 0.13 Mg 0.23 )( Fe 14.68 Al 0.36 )( AsO 4 ) 9 O 15.78 ·25.5 H 2 O , is described. New powder X-ray diffraction and electron microprobe data are provided for type material from Tagish Lake, Yukon Territory, Canada, and that from the new locality, Saalfield, Thuringen, Germany. New chemical formulae are proposed. The strongest reflections are at 14.1(100), 2.79(60), 3.25(57), 5.58(37), 2.61(20), 1.63(20), and 2.24(11) Å.