Among the latest highlights from phase one drilling, the company intercepted 57m at 2.96g/t gold from 99m, and 74m at 1.93g/t from 185m.
CEO Greg McCunn, who rejoined the company in April to take on the role, said as a result of the success, the company was expanding the phase one programme to test the length of the strike along the southwest.
The company said Tontokrom had numerous historic small-scale and alluvial mining operations and was on the Fromenda shear structure, part of the Asankrangwa structure which hosted all nine of the Asanko gold mine's deposits.
Asanko operates the mine, which is 10% owned by the government and the remainder split 50:50 between Asanko and South Africa's Gold Fields, under a joint venture struck last year.
The JV plans to spend US$8 million on exploration this year.
The mine produced 60,425 ounces of gold in the March quarter and Asanko said last month it was on track to achieve 2019 guidance of 225,000-245,000oz.
Asanko shares slid from C$1.50 a year ago to a 52-week low of 80c in December.
They rose 3.57% yesterday to close at 87c, capitalising it about $196 million.