The company announced the discovery of the high-grade zone earlier this month, describing it as "a turning point" for Zinc One as it explores the previously mined project.
Highlights from the latest results from the now-complete 53-hole programme at Mina Chica included 12.7m at 38% zinc from 6m, and 28.5m at 20.1% from 4.3m.
Drilling at the project is continuing with a resource update slated for the third quarter.
The Bongará openpit produced about 150,000 tonnes at 20% zinc in 2007-2008, when it was shuttered due to low zinc prices and the global financial crisis.
The zinc price fell to about US$1,180 a tonne in 2008 and climbed to a 10-year high of $3,606/t on January 2, last trading at $3,043/t on the London Metal Exchange.
Zinc One exercised an option to acquire the Bongará and Charlotte Bongará zinc oxide projects in June 2017, saying it was the first time the two projects 6km apart had been controlled by a single operator.
The company, which changed its name from Rockridge Capital Corp in January 2017, had a working capital deficit of about C$1.03 million (US$0.8 million) at end of November.
Its share price was up C1c to 26c yesterday but remains down about 41% year-to-date, capitalising it at $25.7 million.