Cobalt
Co
atomic number
27
melting point
1495C

1. Mix a small amount of powdered mineral with borax flux, then expose the mixture to either the oxidizing or reducing portion of the flame (in this case, it doesn't matter); the fused bead will take on a beautiful blue color, (the sample must first be roasted on charcoal if sulfur or arsenic are present; this will drive off these elements which tend to obscure the test).

2. Dissolve some powdered mineral sample in a strong nitric acid solution; the solution will turn a beautiful rose-red color; if an excess of ammonia is added to the solution, it will turn brown at first, then slowly back to red.