IMO, Bob's sulphur issue does not pass the smell test. He has been harping about this issue for sometime. Long enough I think for those that just bought the latest cross to investigate if the issue has any merit. Those that just laid out millions would have done some deep DD on all aspects of Zenyatta. Euro Pacific seems to have some educated staff, including Dr. Luisa Moreno PhD MEng. Here is a little on her Bio from the Euro Pacific TO office...

Dr. Luisa Moreno has ten years of experience as a publishing Research Analyst and academic researcher, working primarily in the field of materials science and mineral resources. Few other analysts focus on the technical threshold issues of engineering (e.g. metallurgy and processing) as she does. Her experience and research has focused on the technical and economic study of industrial and specialty materials (e.g. tantalum, rare earths, alumina, bio- and composite materials). ....

If there were any issues such as the one's Bob has raised, it would appear that Euro Pacific and other investment houses have disregarded it.