I've worked as an exploration geo at TC. Those ironstones can be...

I've worked as an exploration geo at TC. Those ironstones can be really tricky to ping with a drillhole. They can be very poddy and only portions of them are mineralised - normally Cu at the top and Au-Bi at the base for the bigger ironstones.

Step out too far from known mineralisation and you'll lose it. Using downhole geophysics for drillhole targetting is painful. A geophysical anomaly can be a few small pods or one big pod - the anomalies look exactly the same.

The ironstones get smaller has you progress north from the Juno - Nobles Nob line where they're biggest, so there's not much joy to the north.