Question

Synthetically made glass and natural quartz crystals both exhibit a fracture pattern termed ________.

1) glassy fracture.
2) conchoidal fracture.
3) one-directional cleavage.
4) obtuse fracture.

Answer 1

Synthetically made glass and natural quartz crystals exhibit a fracture pattern known as a conchoidal fracture, which is a curved surface seen on materials without cleavage.

Step-by-step explanation:

Synthetically made glass and natural quartz crystals both exhibit a fracture pattern termed conchoidal fracture. Conchoidal fracture refers to the way a mineral breaks to form a curved surface, which looks somewhat like the inside of a clamshell. This type of fracture occurs in minerals and materials that lack cleavage, which is the tendency of a mineral to break along flat planes where atomic bonding is weak.

In contrast to minerals with directional cleavage, such as muscovite with perfect cleavage in 1 direction and pyroxene with cleavage in two directions at 90 degrees, quartz has no cleavage and breaks with a conchoidal fracture. Ceramics like CorningWare, which contain amorphous silica, also exhibit this type of fracture without crystallizing, maintaining a random arrangement of SiO4 tetrahedra, characteristic of supercooled liquids.