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A question for heavy metal fans only?

A band for each genre:Traditional Heavy Metal:Thrash Metal:Doom Metal:Stoner Metal:First-Wave Black Metal:Black Metal:Speed Metal:Progressive Metal:Death Metal:Technical Death Metal:Melodic Death Metal:Folk Metal:Alternative Metal:Groove Metal:Viking Metal:

Answer:

Your link is informative and correct. The reflectance is a property of the sea of electrons, which is why you don't get it with the individual ions. Semiconductors (metalloids, remember?) also show luster in the visible region, where the light energy is enough to lift electrons to the empty conduction band, and they then just drop straight down again reemitting the light.
Conducting surfaces have a greater propensity to REFLECT EM radiation including light. It's no accident that silvered mirrors are most reflective ( Ag being the most conductive metal ) with aluminum being a preferred coating for large astronomical mirrors.
Luster Of Metals
There are two sorts of reflection: diffuse reflection and specular reflection. Diffuse reflection is when light rays hit a rough surface, and the light bounces EVERYWHERE. When the light is reflected everywhere, it doesn't look shiny, or lustrous--this is because not enough light is being reflected into your eyes. In specular reflection, the surface is flat and perfect, and the light that hits the surface all bounces in the SAME direction. When all the light travels in the same direction, it all enters your eyes. When the light hits the metal, the reason why a metal would have lustre is because its surface is smooth and perfect (or smooth and flat enough), so the light that hits it is reflected in the same direction and most of the rays enter your eyes. The smoother the surface, the more reflective it is, baby!
All metals can be made to shine. It is not the structure of the base metal which affects the shine over a period of time. It is the oxide layer which forms on the surface. The more active the base metal, the thicker and looser in general the oxide layer. Think iron and red rust. You can shine a piece of iron to a very shiny mirrorlike surface and within a relatively short period of time, the surface will oxidize and the shine will disappear to be replaced with loose red rust. The amount of shininess of the surface of any metal is determined by the oxide layer on the surface, the thicker, the more it obscures reflections from the base metal, The thinner, the more reflected light shines through. Passive metals such as gold, develop an oxide layer but it is tightly cohesive and very thin, which acts to separate the base metal from the environment while being thin enough to allow a significant amount of light to be reflected off the surface so you see the yellow color of the gold. Red rust on the other hand is loose, and does not separate the base metal from the environment so it continues to oxidize and corrode the base metal. Alloys such as stainless steel are passive because of additives which form the oxide layer. In the case of stainless steels, it is chromium, which forms a tight cohesive oxide layer before the steel itself starts to rust. The chromium dioxide layer being tightly cohesive like gold, separates the steel from the environment so it stays shiny.

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