The WKP prospect, 10km north of Waihi, was being hailed as a ''major milestone'' for Oceana and a further 14.5km of test drilling is planned during 2019.
Oceana chief executive Mick Wilkes said the ''significant discovery'' at WKP had the potential to create additional employment opportunities and generate significant socio-economic benefits for the country and communities.
''I'm very pleased to announce this major milestone for the company at our newest high-grade discovery at WKP,'' he said in a statement.
One area at WKP has an estimated indicated resource grading 18g of gold per tonne (g/t) for 234,000oz of gold and 22.7g/t for 296,000oz of silver. The other sector has an estimated inferred resource grading 11.9g/t for 401,000oz of gold and 16.8g/t for 568,000oz of silver.
''For the past year, we've been focused on drilling at the East Graben vein, currently one of three major veins discovered to date,'' Mr Wilkes said in a statement.
He said Oceana's WKP exploration budget had ''increased significantly'' from last year and the target was to drill 14,500m at WKP this year.
Waihi had recently gained resource consents to expand underground operations near the historic Martha pit, and namesake township, which had the potential to add a decade to mine-life.'