Marimaca Copper's (ASX:MC2) Pampa Medina project in Chile may host a potential mineral resource of over 150 million tonnes at a greater than 1% grade of copper, Euroz Hartleys said in a Wednesday note as it raised its previous estimate of around 100 million tonnes.

The upgrade to the investment firm's estimate comes after Marimaca identified further high-grade copper and silver mineralization during recent drilling at the deposit, including 20 meters of 2.7% copper and 13.9 grams per tonne grade of silver from 564 meters.

The drilling extended mineralization into the basement metasediments for the first time at Pampa Medina, and the intersections could indicate opportunity for further extensions, the equity research firm said.

"The recent Pampa Medina sulphide drill intercepts deserve to be appreciated by the market as the project should significantly increase the company's mineral resource inventory in time," Euroz Hartleys said.

It maintained a speculative buy recommendation and AU$16.94 per share target price on Marimaca Copper.

Marimaca Copper's shares fell past 3% in recent Thursday trade.