Thread: Luster of a mineral

Hey guys,

I've been wondering how a material appearance(the way it reflects light) is related to its chemistry? Anyone knows?

Graphite has a certain lustre because the carbon polymerises in planar layers, if I am not mistaken.

Thanks for the reply,

But how does the bonding got to do with its luster, can u explain

Originally Posted by Fakhri_hanes

Hey guys,

I've been wondering how a material appearance(the way it reflects light) is related to its chemistry? Anyone knows?

This is actually a pretty complex question, and depends entirely on the mineral. In very general terms, however, chemical structures absorb certain wavelengths of visible, white light, and what's left over is what you see.

Originally Posted by tenderheart bear

Originally Posted by Fakhri_hanes

Hey guys,

I've been wondering how a material appearance(the way it reflects light) is related to its chemistry? Anyone knows?

This is actually a pretty complex question, and depends entirely on the mineral. In very general terms, however, chemical structures absorb certain wavelengths of visible, white light, and what's left over is what you see.

Thanks for the reply tenderheart bear. But correct me if I'm wrong, isn't absorption of light only reflects its color (I remember reading this somewhere-again if I'm not mistaken :-D ) . Do you guys have any links or books that i can read about this topic?? Thanks


About the color of an element,transition metal in particular, I can't remember exactly how it was produced. The only thing i recalled was it got something to do with the d-orbital . It was only a year ago that i learn this stuff..Can someone also explain this..hehe Thanks

Originally Posted by Fakhri_hanes

Originally Posted by tenderheart bear

Originally Posted by Fakhri_hanes

Hey guys,

I've been wondering how a material appearance(the way it reflects light) is related to its chemistry? Anyone knows?

This is actually a pretty complex question, and depends entirely on the mineral. In very general terms, however, chemical structures absorb certain wavelengths of visible, white light, and what's left over is what you see.

Thanks for the reply tenderheart bear. But correct me if I'm wrong, isn't absorption of light only reflects its color (I remember reading this somewhere-again if I'm not mistaken :-D ) . Do you guys have any links or books that i can read about this topic?? Thanks


About the color of an element,transition metal in particular, I can't remember exactly how it was produced. The only thing i recalled was it got something to do with the d-orbital . It was only a year ago that i learn this stuff..Can someone also explain this..hehe Thanks

According to "Introduction to Mineralogy" by Nesse, Minerals dominated by ionic and covalent bonding are transparent, while minerals with metallic bonding are opaque.

In non-metallic lustre minerals, ~ 5% - 15% of incident light is reflected, submetallics ~ 15-20 "normal" metallics reflect 20%-50% and splendant metallics reflect over 50.

Cleavage planes and texture also have an effect on lustre.

Reflected wavelength is what determines the colour.

Tenderheart Bear is correct, it get's very complicated after that, but if you want to get deeper into the chemistry of colour, have a look at crystal field theory: http://en.wikipedia.org/wiki/Crystal_field_theory, band theory, charge transfer transitions (All covered in Nesse). It's the better part of a chapter, so I'm not going to type it here, but if you have any specific questions, I'd be happy to have a look.

Regards.