hey evry1 i will also put some imp tips and facts related to Q in this forum
FACT1: lapis lazuli is rare mineral having blue colour .Ultramarine is an artificial lapis lazuli.It's a complex of silicate of sodium and aluminium containing 12% sulphur.
FACT2: HUME ROTHERY RULE for complete miscibility
1. the 2 metals must be similar in size .Their metallic radius must not differ [by more than 15%
2. Both metals must have the same crystal structure.
3. the chemical properties of the metals must be similar .In particular the number of velency electrons should be the same.