Speaking at the RIU Explorers Conference, Beckwith suggested other fields such as the 10Moz Southern Cross field were already well in hand, with the company continuing to become "much more confident" it had a "tier one" asset in its grasp.
"We're not hoping it will get bigger, we're expecting," he said in reference to ongoing drill success at multiple prospects currently featuring eight rigs.
A maiden resource estimate for the "high value deposit" is due mid-year.
He also said he was getting very confident De Grey would meet internal resource targets that almost made him "fall over" when they were outlined nine months ago.
Beckwith believes Hemi will be one of WA's largest gold mines when developed.
Regarding the metallurgy issue that's been the other big question around Hemi, Beckwith is similarly confident.
He pointed to the 95%-plus recoveries achieved in early testwork, and said the Albion process "seems to be coming a little bit to the fore" versus the other two processes tested, POX and BIOX.
Either way, "in our minds, it's not a question anymore".