This is indeed possible as glass and sand are both made from the same chemical, silicon dioxide. Silicon dioxide has an extremely high melting point, so first the sand has to be heated past this for it to become a liquid. In sand, the silicon and oxygen atoms are arranged in a very orderly way. When the sand is heated to very high temperatures, this arrangement breaks down and the position of the atoms becomes disorderly and random. If the sand is cooled quick enough, then the atoms of oxygen and silicone don’t have enough time to revert back to their nice orderly arrangement, so they form the substance we know as glass.
When lightning occurs, the strike point can reach temperatures of up to 30,000°C, which is much hotter than the surface of the Sun. Providing the sand is of the right kind then it is possible that glass will form. Fulgurite is the term given to what is left over, which is a hollow glass tube and can sometimes penetrate up to 15 metres below the surface of the sand.
The type of sand the lightning strikes is a major factor as to whether it will turn into glass or not. Meteorite impacts have also been known to release a large enough amount of energy to convert sand into glass. Due to the unpredictable nature of lightning strikes and given that they can be highly dangerous, it might be a risky business opportunity in more than just the financial sense. On average there can be more than 100 lightning strikes happening every second across the globe, but the chances of these being over the right type of sand at exactly the right moment are very low, so don’t get your hopes up!
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