Please Help Identify these rocks!!

[mtjaws88]

I found several of these rocks on my property and I have no idea what they are. I live in the Piedmont region of Georgia and have become familiar with the geology. Ive never seen these rocks anywhere else in the county. All these rocks (over 20 boulders as pictured) were right in the same spot and Ive noticed quartz lines running through several of them. See attachments. Any help would be appreciated. Thank you.

 

[loco oro]

it looks like a quartzite,a morphed sand stone,it could have quartz veins in it just like any other rock.