The Rock Dam Gold Prospect/A New Quartz Locality, Dickinson Co., Michigan

摘要

The Rock Dam gold prospect is located in central Dickinson County, Michigan, approximately ten kilometers north of the village of Quinnesec (See map on page 5). The diggings (test pits and short adits) are developed in outcrops of the Early Proterozoic Sturgeon Quartzite Formation (Marquette Range Supergroup), the dominant exposed bedrock in this part of the county. Excavated near the turn of the 20th century, the prospects themselves are thoroughly unglamorous, yielding neither quartz crystals nor any noteworthy accessory minerals save muscovite and minor pyrite. Of these prospects, Bayley (1904) states that, "some of these quartz veins contain small quantities of free gold, as does also the quartzite in their vicinity." However, newspaper clippings from 1881 wax skeptical, saying that, ". . .quartz has been found and samples assayed which panned out at the rate of 1,000 dollars per ton, or big lies told. We are not quite certain which." (Cummings, 1991).