Copper price reviving old deposits US Copper has mobilised exploration teams to the Superior deposit in California. (Credit: US Copper) The record copper price environment has prompted a resurgence in copper exploration activity at several marginal projects at the long-term metal price average. Just two examples include US Copper Corp (TSXV: USCU; OTCQB: USCUF), which has this week mobilised exploration crews to the Superior copper deposit in California, USA, and Sweden-based Copperstone Resources, which has for the first time in 25 years opened and entered the former Viscaria copper mine si...