The mine, which closed in 1970 due to low copper prices, has a historical resource of 4.7 million tonnes at 1.95% copper, 4.13% zinc, 0.94% lead and 35.9 grams per tonne silver.
"[The maiden resource] will exceed the 4.7 million tonnes," New World managing director Mike Haynes told The Boom in a Room Investor Conference in Perth.
"By how much I don't know."
Still, given the exploration upside, New World sees the upcoming resource as an "interim" number that will underpin mine studies and permit applications.
New World is targeting the start of construction in 2024.
With a copper shortage looming, Haynes said it was important to note that Antler would have a short lead time given its modest size.
New World is targeting a 750,000 tonne to 1 million tonne per annum plant at a grade of about 3% copper equivalent to produce about 30,000tpa of copper equivalent.
"It's not huge but it's very achievable for a junior to dictate our own course," Haynes said.
New World plans to continue exploration while advancing permitting and studies.
Of 78 holes drilled, all but one have intersected copper sulphide mineralisation.
The company believes it may have discovered a third shoot, with recent results of 4.5m at 3.7% copper equivalent and 2.7m at 5.3% copper equivalent.
The target covers 150m of an almost untested anomaly and is open at depth.
"The third shoot could be just the tip of the iceberg." Haynes said.
"We're moving towards having a critical mass that will underpin a standalone operation."
New World shares are trading at a two-month high of A7.6c, valuing the company at $112.6 million.