Help ID Rock/Mineral

[Bidgee]

This rock came from a stream near Tumut NSW. About as big as a small fist. Dominant lithology is the region is granodiorite. It has an usual mineralisation/structure. I'd appreciate any thoughts on what the structure may be. The images are of the main sample plus a fragment I broke off.

TIA

 

[Martin]

It could be Staurolite or Tourmaline.

 

[Bidgee]

It could be Staurolite or Tourmaline.

I've done a bit research and I think they are some type of amphibole within the granodiorite - possibly hornblende. They are striated and triangular in cross section.