The budding producer, which added an underground operation to its Golden Chest openpit operations in November, has acquired the nearby Four Square lease for US$800,000 in cash and shares and a 2% NSR royalty.
The property includes the historic Four Square gold and tungsten mine, and the company has also acquired an adjacent 348 acres of unpatented mining claims through staking.
NJMC had added to its landholdings in January and the latest acquisitions give it control over 5,200 acres on the belt.
"The Four Square property further expands our land position in the Murray Gold Belt, a largely overlooked camp that, we believe, offers excellent potential for large-scale gold production," CEO and president John Swallow said.
The company said Four Square held some similarities to Golden Chest, less than 5km away.
NJMC recorded a gross profit of $1.19 million for 2017, in its first full year of production, compared with about $69,000 in 2016.
It reduced its liabilities by $1.18 million in 2017 and the company anticipates being largely debt-free by the end of 2018.
It processed about 31,350 tonnes at its New Jersey mill with an average headgrade of 4.11g/t and sold 3,525oz for the year.
Shares in the company have virtually doubled in 12 months and reached a 52-week high in January of 18.5c.
They closed down 2.86% yesterday to 17c.