Total resources are now 171Mt grading 10.3% manganese for 18 million tonnes of contained metal, with the update coming just eight months after the last.
Measured resources are now 100Mt at 10.4%.
FB3 is the larger of the two deposits at 116Mt at 10.2%, while LR1 contains 56Mt at a slightly higher grade of 10.4%, while there is a higher-grade component totalling 40Mt at 13% that should support the early years of any development.
Black Canyon is conducting development and feasibility studies for an open pit development in Western Australia's Pilbara region, about 400m from Port Hedland.
It announced the results of a 1.8Mtpa scoping study in August, based on a 36Mt at 11.7% production target, defining a multi-decade mine life with a A$44 million development cost generating $2.3 billion in earnings.
Managing director Brendan Cummins said Flanagan Bore's deposits continued to show a high level of continuity, from outcrop down to about 40m below surface.
Earlier this week Black Canyon lodged a mining lease application, and hopes to be in a position to take a development decision by early 2024.
Studies are also ongoing to assess potential for production of high purity manganese sulphate.
Flanagan Bore is part of the company's Carawine JV, where Carawine Resources is reducing its interest to 25%.
Black Canyon shares were up 10% this morning at 26.5c, capitalising it at $14 million.
The stock has traded at 19-51c over the past year.
The junior has $3 million in cash remaining.
Carawine shares were steady at 8.9c, capitalising it at $18 million.