For clarification on my upcoming post:

Dragons eat precious metals for healthy scale. I say this because it gives them an actual [i]reason[/i] to hoard, beyond greed and love of shininess and wealth. Eat pure gold and iron/steel every day, you'll have thick, strong scale that shines. Eat just iron/steel, you'll probably have thick and strong scale, but it won't be so shiny. Eat just gold, and it'll probably get a little less thick, but would weigh less, and shine brighter than without gold. 

Lead would probably make scale heavier; tin would probably strengthen other metals' attributes.

Is this agreeable with everyone?