Silver’s Compelling Investment Case (Ainslie), page-185

btw - as a useful but very very broad rule of thumb I generally assume say 50% of a total resource will be Measured and Indicated, of which say 70% might get into mineable reserves

its highly specific to each project as to how that shakes out

but as a first pass thats a helpful way to start sorting the wheat from the chaff in terms of getting a sense of whether it could sustain a viable mine

I would expect you want at least 20Moz Ag eq bare bare minimum once you cut it down that way - ie 2Mozpa for 10 yrs

and frankly thats still being extraordinarily risk on