Ashcroftine-(Y)

Ashcroftine-(Y) is an alkali yttrium calcium carbonate mineral with the chemical formula K$5$Na$5$(Y,Ca)$12$Si$28$O$70$(OH)$2$(CO$3$)$8$·8H$2$O. It was first identified in southern Greenland and named after British mineral collector Frederick Noel Ashcroft.