The share prices of SolGold and Cornerstone Capital Resources rose sharply in Canada on Thursday afternoon, following an announcement that the Ecuador mining referendum petition had been dismissed.

TSX-V-listed Cornerstone, which is a partner in the significant Cascabel copper/gold project with Toronto- and London-listed SolGold, said in a statement that the Constitutional Court in Quito had dismissed the petition for a referendum on whether or not to allow the development to proceed.

The petition was rejected because it was imprecise and failed to include, among other things, introductory recitals and failed to satisfy other Constitutional requirements, Cornerstone said, noting that the decision was unanimous and that it could not be appealed.

The court did not examine the merits of the case, the company added.

Under Ecuadorian law individuals were legally allowed to put forward petitions to the Constitutional Court for the inclusion of specific questions in a future vote.

Cornerstone’s stock shot up by 20% immediately after the announcement to C$0.23 a share, but settled at C$0.23 a share later in the afternoon. The share price is yet to regain what was lost since the referendum was first mooted at the end of May.

SolGold’s share price jumped 17% in the late afternoon in Toronto to trade at C$0.54 a share. Its share price is still well below the pre-referendum-talk level of about C$0.65 apiece.

SolGold has previously stressed that it did not believe the Cascabel tenure was not at risk and that it had the “full and objective support” of the Ecuadorian government.

The preliminary economic assessment (PEA) for the Alpala deposit in the Cascabel project indicated that the government and people of Ecuador stood to benefit from $17-billion in taxes, royalties and profit shares.

The PEA for the Alpala copper/gold/silver deposit delivered “outstanding financial metrics”, with a start-up capital expenditure of $2.4-billion to $2.8-billion, a net present value range of $4.1-billion to $4.5-billion, at an 8% discount, and an internal rate of return of between 24.8% and 26.5%.

The study has put forward four production cases, ranging from 40-million tonnes a year to 60-million tonnes a year, with an estimated mine life of between 49 years and 66 years. Based on the 50-million-tonne-a-year mining scenario, the Alpala deposit is estimated to produce 207 000 t/y of copper, 438 000 oz/y of gold and 1.4-million ounces a year of silver in concentrate in the first 25 years of operations.

The project will produce high-quality concentrates (28.2% copper, 22.1 g/t gold and 65.7 g/t silver), which should deliver a sales premium for the concentrates.