You wouldn't be able to know how many years exactly from the core drilling visuals, for that you'd need to assay the cores for the grades, build a mining block model and then develop a mining plan from that. It's more of a qualitative "oh dam they've struck gold a lot of it" sort of thing that would move markets. Disclosures to markets in mining need to be done publically and with proper backing of data, legacy of BreX salting their core samples and reporting the motherload of gold mines.