Sierra Metals (TSX:SMT) Here’s a look at those companies and the factors that moved their share prices last week. 1. Marimaca Copper Marimaca Copper’s company name aligns with its flagship development asset in Chile, the Marimaca project, which is one of the largest copper discoveries in Northern Chile. Last Thursday (April 22), the company announced the definition of a new, large-scale copper geochemical anomaly at the Roble target, which it plans to drill test over the coming months. Marimaca saw its share price go up by 25.39 percent last week to reach C$5.63. 2. CNOOC CNOOC is the largest producer of offshore crude oil and natural gas in China, and is one of the largest independent oil and gas exploration and production companies in the world. CNOOC mainly engages in the exploration, development, production and sale of crude oil and natural gas.