Mick, those are nice rocks - the ballast is mostly slag from smelting operations (but on the other side of the tracks) and recycled concrete (including granite countertops). It's a bit of a mess.
Hasselblad 501c with 80mm f/2.8 lens and Minolta IV light meter
Kentmere 120, 400 rated at box speed
Exposure was 1/250th at f/19
Developed using Barry Thornton's two-bath D23 and sodium metaborate at 72.5F/22.5C
Multitone RC pearl paper exposed for 10.5 seconds at f/22 with a 2.5 Ilford Multicontrast filter and developed in Liquidol 1:9, Sprint vanilla stop and Hypam fixer