Possible Clues:

• Valuable silvery metal
• 24 down girl, one not feeling capital on getting lost in picture
• Metal coating no good - useless material, primarily
• Gray-white element
• Precious metal; sort of blonde
• Silvery-white metal
• Jewellers' metal is highly desirable (a base metal's in it)
• Atomic No. 78
• A container in very good metal
• Desirable to coat a cheap metal or an expensive one