Los Cuarentas


Sold to Riverside Resources for cash, shares, and a royalty on June 26, 2019.

June 26, 2019 – Millrock To Sell Mexico Assets


Los Cuarentas is a low sulfidation epithermal Au+Ag target characterized by strong argillic and phyllic alteration surrounding low sulfidation epithermal vein systems that host gold and silver mineralization. Vein textures and silica polymorphs suggest that the higher levels of the epithermal systems are present throughout the under-explored district. Hydrothermal alteration is overprinted in places by strong oxidation after pyrite and other sulfides. Several target zones have been identified and most are ready for drilling; these are named: Santa Rosalia, Santa Rosalia Sur, El Sombrero and El Chapo.

Location and Setting

The property is located in northern Sonora, 170 km northeast of Hermosillo near the El Mercedes mine (operated by Premier Gold Mines) and the Las Chispas epithermal gold project (operated by Silvercrest).


Millrock holds a 0.5% net smelter returns (“NSR”) royalty on the project.