Ruthenium
This is the most refractory of all metals except osmium. It has, however, been fused in the oxyhydrogen flame. Ruthenium is scarcely attacked by nitro-muriatic acid. After fusion it has a density of 11.4. See METALS.
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This is the most refractory of all metals except osmium. It has, however, been fused in the oxyhydrogen flame. Ruthenium is scarcely attacked by nitro-muriatic acid. After fusion it has a density of 11.4. See METALS.