The distance from Ball Eye and the fact that it is on the opposite side of the valley makes it very unlikely. Dean Quarry is over a kilometre from Silver Eye. However, some of the Silver Eye workings do intersect natural fissures (for instance there is a working off the right hand passage at the top of the spiral climbing way, not shown on the 1971 Flindall and Hayes survey, that connects with some fissures loosely filled with rock) and I suppose these theoretically could connect with the surface over some distance.