Why we can see through glass.

In the answer to “How come we can see through glass” it says that we can see through glass because it is an amorphous liquid.

If this is true then why can we see through Ice, isn’t that a solid? If not, does that mean that if we were to lower the temperature enough to make glass or ice a true solid, would we not be able to see through it anymore?

I meant to say viscous liquid, considering all liquids are amorphous.

And if people are going to harass me about amorphous solid and highly viscous liquid, I say tomato you say tomaato. Big difference.

And the column is, How come you can see through glass?

I’ll let someone else explain it. :smiley:

This discussion was held here already. The upshot is that:

(1) glass is a solid, so Cecil was wrong.
(2) amorphousness has nothing to do with seeng through it, so Cecil was wrong.
(3) Hi, Opal! (Cecil didn’t discuss this).

None of this has anything to do with anything. Transparency in the visible spectrum is unrelated to a substance’s hardness or state of matter (solid,liquid,gas [so long as the substance is not hot enough to be emitting visible light] ) .

Many materials are crystalline powders, and you can’t see thru those. If you grow large crystals, many of those will be transparent. Even powders can sometimes be pressed to a hard transparent material.

Glass is a liquid, so Cecil was right and you were wrong. It’s just very, very viscous, but it does move very slowly. If you were to go to a house that is very old (maybe 50-100 years or older) and took out an original window pane (this is assuming they haven’t been changed over the years) you would see that the top of the glass is significantly thinner than the bottom. This is because the glass as been slowly dripping down. It seems to be solid, yes, but it is actually liquid.

mighty, please take the time to read through the Glass - liquid or solid? thread to which nametag already linked. Glass may be an amorphous solid or it may be a glass, but it is not an over-viscous liquid. There are numerous citations on that thread explaining and documenting that point, including a reference to the original work, the mistranslation of which started the whole silliness about “liquid glass.” (The erroneous claim that glass windows in older buildings has flowed is also debunked.)

Welcome to the SDMB, ShadoWolf, and thank you for posting your comment.
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I think that a better question to ask is “why can’t we see through other solids?” There are two reasons that I can think of.

  1. Scattering.

Scattering occurs at the interface between two phases or materials. Most solids that we look at are not uniform materials. Wood for example is made up of cells which in tern are made up of organelles which themselves are made up of various lipophilic and hydrophilic structers. Paint is made up of microscopic coloidal particles. Brick is made up of tiny rocks which are intern made up of small crystals which may have cracks and idefects in the crystal.
On reason you can see through glass because it is a single uniform material. Imagin what glass would look like if it were powdered. It would be a white powder much like salt or baking soda. Put a single perfect crystal of salt under a microscope and you will see that it too is trasparent (It would be cloudy, but that is mostly due to defects in the crystal.) The same is true for just about any perfectly uniform material.

  1. Absorption: A few compounds absorb light in the visible spectrum. This is due to electronic transitions that are specific to the compound. These compounds will appear colored rather than cloudy, and if the absorption is weak enough, you will still be able to see through them.