Downside, a decline is a tunnel pitched at a 1 in 8 or...

Downside,
a decline is a tunnel pitched at a 1 in 8 or occassionally 1 in 7 for truck/rig access. (the modern version of a shaft!).

Costs between $3 and $4,000 a metre as a guide. A one k decline will set you back $3-4million. They will put in drill platforms on the way down (an area wide enough to turn around in).

Similar methodolgy used at BDG and BGF. Gives better drill access and lets you play around with bulk samples for test work/early development. But it is expensive and does not guarantee success-a fickle narrow high grade reef is what she was and will always be IMO.

Cheers,TAS