Skip to main content
U.S. flag

An official website of the United States government

Multi-element geochemical analyses of samples from the Mesoproterozoic Nonesuch Formation and Copper Harbor Conglomerate at the Copperwood copper deposit, Western Syncline, Michigan, USA

February 23, 2021

This data release provides multi-element data for drill core samples from the Mesoproterozoic Nonesuch Formation and Copper Harbor Conglomerate at the Copperwood copper deposit, Michigan, USA. Copper was determined by assay, and sulfur by inductively coupled plasma-optical emission spectrometry (ICP-OES) after aqua regia digestion for most samples. Multi-element whole rock analyses were determined for selected samples. The Copperwood copper deposit is a sediment-hosted stratiform copper deposit in the Presque Isle Syncline of the Upper Peninsula of Michigan. The deposit has a 2018 mineral resource estimate of 42.2 million metric tons (Mt) of measured plus indicated mineral resources in the Lower Copper Bearing Sequence at an average grade of 1.60 percent Cu and 3.84 grams per ton (g/t) Ag. The measured plus indicated mineral resource in the Upper Copper Bearing Sequence is estimated to be 7.1 Mt at an average grade of 1.21 percent Cu and 3.26 g/t Ag (Gignac, 2018). The mineral reserves for the Copperwood Project are estimated at 25.4 Mt at an average grade of 1.43 percent Cu and 3.83 g/t Ag (Gignac, 2018). Reference: Gignac, L.P., 2018, Feasibility Study Copperwood Project Michigan, USA, NI 43-101 technical report prepared for Highland Copper Company Inc. [Effective Date June 14, 2018]: G Mining Services Inc., 468 p., accessed September 13, 2019, at https://docs.wixstatic.com/ugd/62921a_41a8193d4db1498e8a2d5b1d1391308f….