Why doesn't aluminium powder "shines" as

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Just to be clear by what I meant by metal form

I think it's because the surface is so rouge as apposed to the solid metal which will usually have a very smooth surface. Rough surfaces tend to cause light to bounce off randomly and makes it look darker, whereas the smooth surface of cast aluminum will give a nice reflection.

Freshly ground aluminum will also have no oxide layer formed yet, so if you wait a little bit it might start to look more reflective

The surface of the "metal form" is pretty flat, or flat enough to reflect light like this.

>>9085860
I think the oxide layer also plays a part though, because aluminum oxide is a lighter color than aluminum

>>9085840
Because Aluminum Oxide isn't shiny

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>>9085840
Same with most other shiny materials. Surfaces need to have smooth regions to be shiny.

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Hmm, nice. Do you guys happen to know any other material that "changes" color when powderized? The only other thing I can think of is glass, pic related

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Iron has a stark difference. Powdered iron is quite different from polished iron.

>>9085840
It reflects the light in all directions rather than just one.