yellow ochre - set of 5 tubes of this natural pigment
Yellow ochre forms from the weathering of limonite. This yellow ochre has been screened but is otherwise as collected. It comes from the Whiteside Mine, a former silver and lead mine in Inyo County, California. This mine shipped ore in 1925 & 1929 that was 26.8% lead and which also contained 14 ounces of silver per ton. The underground workings were comprised of around 2,000 feet of adits and a 50 foot shaft. Limonite naturally has water attached to its molecule. The amount of water is variable, and as it increases the limonite alters from hard, brown and vitreous to soft, earthy and mustard yellow, forming yellow ochre. Limonite is common at the top of metallic veins. As it weathers it stains the surface yellow brown. Prospectors examined the rock under this "iron hat" for the economically valuable metals lurking below. Here the area of economically valuable ore was limited and mining became unprofitable. In some areas at the surface of the vein the limonite has weathered enough