There's GOLD Hidden in Old Mining Waste

Outside Johannesburg there are yellow hills made of old mining waste, and they still hold gold. One operation has pulled several tonnes a year out of them for decades. So why did the miners leave it behind, and why isn't it free money? In this documentary we look at why old mills left gold in their tailings (gravity, mercury, early cyanide, coarse grinding and refractory gold locked in pyrite), and at the three numbers that decide whether a dump is a mine: grade, recovery and economics. Then we look at the projects that made it pay, like ERGO on the East Rand and Kaltails in Kalgoorlie, the ones that struggled, like Mintails and the original West Rand tailings plan, and why tailings are both an environmental liability and a possible source of critical minerals. 🎂 GEOLOGY BIRTHDAY CARDS & FIELD TEMPLATES Know a geologist, miner or rock lover with a birthday coming up? I make digital birthday cards and field templates for them, ready to download: 👉 https://www.etsy.com/shop/GeoFieldPro ⏱ CHAPTERS 0:00 Gold in the mine dumps 0:39 The streets paved with gold 3:18 Grade, recovery and economics 5:46 The dumps that paid 7:27 The dumps that didn't 9:25 Tailings: liability and resource 11:14 Why the yellow hills still hold gold 📚 SOURCES DRDGOLD FY2025 results, Mining Weekly (Aug 2025) https://www.miningweekly.com/article/... DRDGOLD H1 FY2026 results, Creamer Media (Feb 2026) https://newsletter.en.creamermedia.co... "Ergo a winner for DRDGold," Miningmx https://www.miningmx.com/news/gold/15... Kaltails case study, tailings.info https://tailings.info/casestudies/kal... "Streets paved with gold," Western Australian Museum https://museum.wa.gov.au/explore/wa-g... "Mintails collapse: case study in how not to close mines," Oxpeckers (2018) https://oxpeckers.org/2018/08/mintail... West Rand Tailings Retreatment Project, Engineering News (2016) https://www.engineeringnews.co.za/art... Far West Gold Recoveries project, Mining Weekly (2019) https://www.miningweekly.com/article/... Mount Polley tailings dam breach, Government of British Columbia https://www2.gov.bc.ca/gov/content/en... Critical minerals in US mine waste, Colorado School of Mines (2025) https://www.mines.edu/news/all-news/2... USGS Fact Sheet 2025-3026, "Critical Minerals in Mine Waste" https://pubs.usgs.gov/publication/fs2... Figures in the worked example are rounded and for illustration only. This video is educational, not investment advice. 🌍 Earth Below explores what's inside the planet, how people find it, and how they dig it out. Subscribe for the next one: how you close a mine for good. #gold #geology #mining gold in mine tailings,gold in mining waste,mine tailings,tailings reprocessing,gold mine dumps,gold recovery,geology facts,economic geology,gold mining documentary,Witwatersrand gold,Johannesburg mine dumps,DRDGOLD,ERGO,Kalgoorlie,Kaltails,refractory gold,cyanide process,cut-off grade,grade vs recovery,acid mine drainage,tailings dam failure,Brumadinho,Mount Polley,critical minerals,gold prospecting,geology documentary,mining history,Earth Below