Pengaruh penambahan aditif kalsium oksida dengan variasi 20, 40, dan 60 wt.% terhadap produk roasting terak ferronickel pada temperatur 900 dan 1100 oC = The effect of addition of calcium oxide with variations of 20, 40, and 60 wt.% on ferronickel slag roasting products in 900 and 1100 oC temperatures