21. Much of the terrain is still loose dirt, interspersed with sandstone and occasional quartz veins . 22. The quartz vein mines became depleted around the time Idaho became a state in 1890. 23. Big Hurrah originally opened in 1908, an underground mine exploiting large quartz veins cutting black slates. 24. The main quartz vein is at least } } long and up to } } wide. 25. Auriferous quartz veins were subsequently found in surface exposures at the site of the current open pit. 26. It is found in sulfide bearing quartz veins in Colorado and with siderite-rich cryolite in Ivigtut, Greenland. 27. Badakshan is the largest and most studied of the known gold-bearing quartz veins systems in the region. 28. AD 500 700 and is slate, with quartz veins and measures 132 ?51 ?13 cm. 29. It crystallizes in the tetragonal crystal system and forms as rounded dissemations within tetrahedrite in quartz veins . 30. Mineralization produced gold-bearing quartz veins , and relics of past gold mining activities are still present in the area.
