Shape | Forward Up (Beginning Observations) Main Page |
 | Shape is an
important factor in identifying particles. The internal crystal structure
of crystalline materials generally influences the external shape. Look
for example at crystals of table salt with a magnifying glass. Its  cubic
internal structure is reflected the tiny cubes you see. Non crystalline
materials will also have important shape characteristics. For example,
glasses have conchoidal glassy fractures (as do some crystalline
materials). Shape may also distinguish between different forms of the same
material, for example, natural chalk (ground shells), ground limestone or
synthetic ( precipitated) calcium carbonate. |