When these rocks break down into the grains that make up the sand on our beaches, their colour is mostly determined by the presence or absence of iron.
当岩石分解成为颗粒够成沙滩时,颜色则是由铁元素氧化物的存在与否决定的。
2
Granulated slag (slag sand) from the manufacture of iron or steel.
冶炼钢铁所产生的粒状熔渣(熔渣砂)。
3
In addition there are limestone iron ores andalusite quartz sand and kaolin etc.