In an announcement yesterday, which follows an earlier retracted "glimpse" of the project's potential, it said the measured and indicated resource for the Buckreef Shear Zone now stood at 45.88 million tonnes at 1.59g/t gold for 2.34 million ounces, with inferred at 9.9Mt at 0.63g/t for 39,190oz, using a 0.4g/t cut-off.
The company said using a 0.5g/t cut-off, the updated measured and indicated resource for the Buckreef Shear Zone came up to 40.9Mt at 1.73g/t for 2.27Moz, more than double the previously estimated 1.08Moz.
"Although the doubling of the gold resources categorised in accordance with the requirements of 43-101 is most satisfying, the interim results we have released today are pointing us in the direction of further increases," executive chairman James Sinclair said.
Tanzanian Gold outlined potential exploration targets of about 482,000oz at the Northeast Extension and 1.7Moz at the Main Zone.
Sinclair said the company had already started a phase three deep drilling campaign.
It has the right to earn 55% of the previously-mined project from the Tanzanian State Mining Company.
A 2018 pre-feasibility study had estimated about 822,000oz of gold would be produced over 16 years, for initial capex of US$76.5 million, with an after-tax NPV5 of $130.96 million and an IRR of 74%.
The company, which also has an NYSE American listing, raised US$3.85 million in December at 57.5c per share.
Its Toronto-quoted stock, which had touched a 52-week low of C56c on Monday, closed up 36.7% yesterday to 82c to capitalise it at $129.8 million (US$91.6 million).