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(first time poster, I can't believe it.)
Awesome post. I'm assuming that the diagram for the amorphous glass is for regular old "float" glass. But if you temper it via quick cooling, does it look more like your first diagram? If this is so, is that because the inner atoms that make up the glass and is still flowing, line up based on the atoms from the outer cooled surface? What if the tempering is completed using compression/ion exchange?

Reminds me of something I read once about using strands of uncooked spaghetti for research in the way certain structures fractures. If you snap a piece of spaghetti it will never just break into two pieces.

No, glass is a ceramic and is composed of oxides, which is vastly different from metals in its structure. The above diagrams are appropriate for metals but not for ceramics. Silica glasses have short-range order, so it's best to think of them as rings of alternating Si and O atoms. Whereas an ice crystal would be formed of perfect hexagons, these rings of Si and O do not have such a pattern, thus making it have no long-range order.

What tempering glass does is it induces stresses within the glass due to thermal expansion. By rapidly cooling the outside of the glass, you do not allow it time to contract. Thus, when the glass inside cools more slowly, it attempts to contract and starts to pull at the surface of the glass (although these are referred to as compressive stresses). It makes the glass stronger because now when you want to break the piece of glass, you must first overcome these stresses (thus taking it to a "neutral" state) and then can you "begin to break the glass", if you will.

Ion exchange does a similar thing, but instead it induces these stresses by taking advantage of the difference in size between Na and K ions. These ions are very large compared to Si and O and sit in the interstitial sites (that is, the center of the SiO2 rings).

You are 100% right about the difference between metallic and ceramic glasses. Since the blog is about metallic glasses, I thought it was easier to illustrate the disorder idea with the metallic picture. I actually started out with a Si-O model, but the picture looked more confusing than helpful, so I retreated back to the simpler metallic picture.

You've both been really helpful. Thanks.

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    • Heavy G
      The perfect pick-me-up when gravity gets you down.
      2 oz Tequila
      2 oz Triple sec
      2 oz Rose's sweetened lime juice
      7-Up or Sprite
      Mix tequila, triple sec and lime juice in a shaker and pour into a margarita glass. (Salted rim and ice are optional.) Top off with 7-Up/Sprite and let the weight of the world lift off your shoulders.
    • Listening to the Drums of Feynman
      The perfect nightcap after a long day struggling with QED equations.
      1 oz dark rum
      1/2 oz light rum
      1 oz Tia Maria
      2 oz light cream
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      1/8 tsp ground nutmeg
      In a shaker half-filled with ice, combine the dark and light rum, Tia Maria, and cream. Shake well. Strain into an old fashioned glass almost filled with crushed ice. Dust with the nutmeg, and serve. Bongos optional.
    • Combustible Edison
      Electrify your friends with amazing pyrotechnics!
      2 oz brandy
      1 oz Campari
      1 oz fresh lemon juice
      Combine Campari and lemon juice in shaker filled with cracked ice. Shake and strain into chilled cocktail glass. Heat brandy in chafing dish, then ignite and pour into glass. Cocktail Go BOOM! Plus, Fire = Pretty!
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      Dr. Strangelove's drink of choice.
      3/4 Triple sec
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      2-3 drops Grenadine
      Fill shot glass 3/4 with Triple Sec. Layer Bailey's on top. Drop Grenadine in center of shot; it should billow up like a mushroom cloud. Remember to "duck and cover."
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