@ Jed, g'day mate, not sure what the powdery white material is, it's chalky and quite soft, the bit on the top right is quartz that much I do know, and it all came from the same fracture seam.
@ the Duck, you hit it on the head mate, was a small fracture seam, followed it down until it disappeared from the detector to about 1.5 metres. Not sure if these seams stop and start tho. Would be interested in hearing what anyone else knows about chasing stringers, tho.