1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
natulia [17]
2 years ago
13

Minerals have a crystal structure, yet, crystals are relatively rare. What are the reasons for this?

Biology
1 answer:
Licemer1 [7]2 years ago
3 0

Answer:

What are relatively rare are crystals of a size visible to the naked eye, and also showing most of the faces that reveal the internal symmetry of their atomic pattern.

Explanation:

Being crystalline, i.e. having a regularly repeated three-dimensional atomic pattern, does not mean that a mineral necessarily formed under conditions where it could nucleate (i.e. assemble as the tiny cluster of atoms that is the “seed” of a single crystal) and keep growing large flat faces until a regular shape becomes visible to the observer.

To a crystallographer who can seek proof of internal atomic order by X-ray diffraction, the actual size of a solid made of highly ordered matter is irrelevant. Specific techniques (variants of X-ray diffraction methods, or polarizing microscopy) can reveal that a solid material is made of a single crystal (i.e. a uniform atomic pattern is repeated in the same orientation anywhere throughout the solid) or consists of many crystals (the same pattern occurs, but it is oriented differently in what are considered individual crystals regardless of their individual shape or size).

For precision, a crystallographer or a mineralogist will use terms such as “monocrystalline” (the atomic pattern has a single orientation throughout the entire specimen, regardless of shape and size) and “polycrystalline” (the specimen is an aggregate, or collection, of “domains” or “grains” in which the atomic pattern is in an orientation different from its neighbours).

A perfect single crystal of quartz, broken in several chunks, doesn’t lose its internal atomic pattern, only its external “habit” (the overall shape imparted by the flat faces that grew, layer by layer, along directions controlled by the rate of addition to the atomic pattern). Each individual broken chip of quartz is considered “monocrystalline” by the mineralogist, even if none ofo them is the whole original crystal.

Most igneous and metamorphic rocks are polycrystalline, i.e. entirely made of crystals, often tightly packed and interlocked. You may discern individual grains mostly when light reflects off surfaces exposed by breaking along preferred directions within some minerals, or because grains from different minerals contrast in colour or luster. Few of the grains will have a regular geometric shape, despite each one being a single crystal. In the case of an igneous rock, some of the well-formed crystal are typically minerals who grew early from the still-liquid magma. Most of the other minerals simply filled the remaining space. If an igneous magma was “gassy” or “watery”, those volatiles may have remained trapped in the last stages of crystallization and formed late pockets in which a few crystals of exceptional quality grew from the remaining dilute magma and had the space needed to fully develop perfect faces. In many rocks, it is later fractures that provided an “open space” in which crystals could grow larger and with well-developed faces from hydrothermal fluids (overheated ion-rich waters), for the future delight of collectors.

You might be interested in
Rick, an athlete, notices a ring shaped inflammation around his neck. Which medication can treat this problem?
Dmitriy789 [7]

Answer:

Ring shaped inflammation would make me think ringworm. In which the answer would be Antifungal as you can buy OTC antifungal cream for relief.

Explanation:

6 0
3 years ago
The dust bowl was the result of a series of dryers drought in the 1930s Where millions of pounds of topsoil were desiccated and
o-na [289]

Answer:

B) Absence of native grasses

Explanation:

The grasses, which acted as a windbreak and whose roots anchored the soil in place, were overgrazed and/or removed to allow for farming. Once a few years of severe drought affected the area, any wind storm was able to blow the topsoil away, rendering the farm land of the Great Plains virtually unusable in many areas. Ground cover is an essential part of sustainable agriculture.

6 0
2 years ago
(02.03 HC)<br> Explain how science uses fossil evidence to support the theory of evolution.
nevsk [136]
The fossil record shows a sequence from simple bacteria to more complicated organisms through time, it is very reliable because it is physical evidence and by studying fossils, scientists can learn how much (or how little) organisms have changed as life developed on Earth.
8 0
3 years ago
11. Name 3 some sources of CO2.<br><br>​
nlexa [21]
People, coal, and gasoline are sources of CO2
7 0
3 years ago
2.<br> What type of sugar molecule is found in a DNA molecule?
Gnoma [55]

Explanation:

deoxyribose

it's a carbon based sugar molecule

4 0
2 years ago
Read 2 more answers
Other questions:
  • Which of the following actions would be most likely to increase the protection of ecological systems in national forests?
    7·1 answer
  • Hich kind of biologist would most likely study whales?
    9·1 answer
  • Last one:
    15·1 answer
  • Bacteriophage in a sentence
    10·1 answer
  • Which is one of the most important differences between prokaryotes and eukaryotes?
    9·1 answer
  • What is the function of the lymphatic system?
    8·2 answers
  • Please look at the picture above.
    11·1 answer
  • Deep vein thrombosis
    7·1 answer
  • The network of connective tissue fibers which pass through the tissues of the body and allow for the efficient movement of immun
    7·1 answer
  • Biological anthropologists view how humans come to be the way they are as the result of Group of answer choices their biological
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!