The prospect includes the Kitano mine and lies within a 7 by 4 km gold district which hosts seven additional gold prospects.
The Kitano mine produced more than 96,000 ounces of gold at an average grade of 5.9 g/t primarily from shallow open-pits before it was closed by the Japanese government in 1943.
Geophysics and sampling have refined the understanding of the geology of the prospect, said the firm.
"It is now interpreted that the western part of the Kitano-o Prospect represents the 'lateral outflow' of a large epithermal system, developed at depth in the eastern part of the 3 kilometre long prospect," the company said.
Meanwhile, a Phase 1 program of drilling consisted of six holes at the western side of the 3 km long prospect over a 750-metre strike length.
"Significant zones of quartz veining were intersected corresponding to those mapped at surface, however, the low tenor of gold reported from drill core assays does not adequately reflect the over 96,000 ounces of gold mined from the exposed paleosurface sinter deposits in the open pits," said Japan Gold.
"The phase 1 scout drilling at the Kitano-o Prospect has provided us with a clearer understanding of this large epithermal system," said John Proust, chairman and CEO at Japan Gold.
"In combination with the newly acquired CSAMT and gravity geophysical data, and previously announced high-grade gold and antimony results in surface sampling, we are now focused on drilling targets in the eastern part of the Kitano-o Prospect to discover the source of the Kitano-o Mine gold."
Focus turns to eastern side
The eastern side has now been earmarked as a key target area for Phase 2 drilling, not least due to the fact that rock samples collected here show high gold and antimony values.
This potentially indicates higher temperatures of deposition and closer proximity to the 'upflow' or 'boiling zone' where gold was precipitating, the firm said.
Japan Gold holds a portfolio of 24 gold projects spanning the three largest islands of Japan - Hokkaido, Honshu and Kyushu.
Its assets cover areas where there are known gold occurrences, a history of mining, and are prospective for high-grade epithermal gold.
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