Here's why:

* Medicine Glass: Quartz is a key ingredient in borosilicate glass, which is known for its heat resistance, chemical durability, and clarity. These properties make it ideal for medical applications, such as vials, syringes, and lab equipment.

* Fireworks: Quartz, in the form of silica sand, is used as a binder and oxidizer in fireworks. It helps to hold the other ingredients together and contributes to the burning process, producing bright flashes of light and color.

So, although quartz is a common mineral found in the earth, it plays a vital role in both the medical and entertainment industries.