As reported at the end of February, the firm is issuing up to 4.8mln units at 25 cents each.
The net proceeds will be used to finance Tethyan's planned advancement of the Rudnitza copper-gold porphyry prospect in 2018, as well as other earlier-stage prospects towards the identification of new drill targets and for general working capital, it said.
Southern Arc Minerals Inc aims to invest C$360,000 to acquire 1.44mln units in the fundraise.
Southern Arc currently owns 29.89% of Tethyan on an undiluted basis and it will not exceed 29.99% on closing of the placing.
Each unit consists of one share and one-half of a share purchase warrant.
Each whole warrant will be exercisable into one company share at 35 cents for three years from the closing date.
Last week, the Eastern Europe-focused explorer updated on its acquisition of Taor - a firm which holds ground adjacent to its optioned Suva Ruda licence in Serbia, saying it had set the date for a shareholder meeting to approve the deal.
Shareholders will also vote on an increase to the firm's share capital.
The meeting will take place in London at 12 pm on 18 May 2018, it said.
In Toronto, Tethyan shares were unchanged at C$0.33.