Question

What makes a glass different from a solid such as quartz? Under what conditions could quartz be converted into glass?

Answer 1

Understand the structure of glass as well as quartz. The type of arrangement of the respective atoms and the type of solid can be a distinguishing factor between glass and quartz. Based on that you can also determine how quartz can be converted into glass by changing the surrounding conditions like temperature, pressure, etc.

Complete answer:
Quartz is a hard and crystalline mineral composed of mainly silicon and oxygen atoms. These atoms exist in a continuous link framework of $Si{{O}_{4}}$ tetrahedra. Each oxygen is being shared between two units of $Si{{O}_{4}}$.Quartz is considered to be the second most abundant mineral in Earth's crust after feldspar. On the other hand, glass is considered to be a non-crystalline and often amorphous solid. It has a widespread practical, technological and decorative use in various fields. Glass is often formed by the rapid cooling of the molten form; few glasses such as volcanic glass are naturally occurring. However, glass on a commercial basis is prepared from silica or silicon dioxide. When we compare the two solids, we see that quartz is a crystalline solid with relatively long-range order and glass is amorphous solid with short range order and has a tendency to flow.

When quartz is heated, it can be easily converted into glass.

Note: It is important to know that although quartz can be heated to form glass, the reverse reaction is not possible. This means that glass upon cooling cannot form quartz as the heating of quartz is an irreversible chemical reaction.