. "gold-bearing quartz" . "Quartz reef mining" . "Quartz reefs" . "Quartz reef mining" . "quartz gold" . "Gold reefs" . . "drifting" . "reefs" . "gold reef" . "quartz vein mine" . . "quartz reefs" . "gold quartz" . "reef" . "quartz reef mining" . "quartz reef mines" . . "quartz mining" . .