Chapter 5 Patterns in Nature: Minerals
5.2 What is a mineral?
“A mineral is a naturally occurring solid, formed by geologic processes, that has a crystalline structure
and a definable chemical composition.”
I. Naturally occurring: Formed in nature, not in factories. Those made in factories are called
synthetic minerals.
II. Formed by geologic processes: Processes that did not involve living organisms. So;
solidification of molten rock or precipitation from a water solution. Minerals produced by
III. organisms are called biogenic minerals.
IV. Solid: A state of matter that will not conform to the shape of its container. 1 Not liquid or gas
V. Crystalline structure: Atoms that make up a mineral are fixed in a specific, orderly pattern.
The framework is called the crystal lattice.
VI. Definable chemical composition: It is possible to write down a chemical formula.
Inorganic: Not organic. Organic chemicals consist of molecules that include carbon-carbon
and/or carbon-hydrogen bonds. (C-C or C-H), and either form in living organisms or have
structures to those that formed in living organisms. But there are some exceptions.
Distinguish between a mineral and a glass; a mineral is crystalline while glass is not. This means that
the atoms, ions or molecules in a mineral are ordered into a crystal lattice.
5.3 Beauty in patterns: Crystals and their structure
1 Container= vat
, A crystal is a single,
continuous piece of
crystalline solid,
typically bounded by flat
surfaces called crystal
faces that grow naturally
as the mineral forms.
The angles between
crystal faces are the
same as the angle of
another face, at the same
flat structure.
Structure of a
crystal
By
using an X-ray beam passing through a crystal breaks up into
many tiny beams to create a pattern of dots on a screen.
Physicists refer to this phenomenon as diffraction; it occurs
when waves interact with regularly spaced objects. So, atoms
within a crystal must be regularly spaced, and the spacing
must be comparable to the wavelength of X-rays.
Crystal structures are always symmetrical. Since
anions have extra electrons they tend to be bigger than cations, so in minerals with ionic bonding
cations tend to nestle snugly in the spaces between anions in many crystal structures so that as many
anions fit around a cation as there is room for.
Anion= negative charge --> extra electrons, so bigger
Cation= positive charge --> less electrons, so smaller
Same groups of atoms/ions/ionic molecules can be arranged in more than just one way. A mineral that
have the same chemical composition but different crystal structure is called a polymorph.
Formation of minerals
1) Solidification of a melt
2) Precipitation from a solution =atoms/molecules/ions dissolved in water bond together and sepearte
out of the water
3)Solid-state diffusion = the movement of atoms or ions through a solid to arrange into a new crystal
structure
4) Biomineralization= living organisms cause minerals to precipitate either within or on their bodies or
5.2 What is a mineral?
“A mineral is a naturally occurring solid, formed by geologic processes, that has a crystalline structure
and a definable chemical composition.”
I. Naturally occurring: Formed in nature, not in factories. Those made in factories are called
synthetic minerals.
II. Formed by geologic processes: Processes that did not involve living organisms. So;
solidification of molten rock or precipitation from a water solution. Minerals produced by
III. organisms are called biogenic minerals.
IV. Solid: A state of matter that will not conform to the shape of its container. 1 Not liquid or gas
V. Crystalline structure: Atoms that make up a mineral are fixed in a specific, orderly pattern.
The framework is called the crystal lattice.
VI. Definable chemical composition: It is possible to write down a chemical formula.
Inorganic: Not organic. Organic chemicals consist of molecules that include carbon-carbon
and/or carbon-hydrogen bonds. (C-C or C-H), and either form in living organisms or have
structures to those that formed in living organisms. But there are some exceptions.
Distinguish between a mineral and a glass; a mineral is crystalline while glass is not. This means that
the atoms, ions or molecules in a mineral are ordered into a crystal lattice.
5.3 Beauty in patterns: Crystals and their structure
1 Container= vat
, A crystal is a single,
continuous piece of
crystalline solid,
typically bounded by flat
surfaces called crystal
faces that grow naturally
as the mineral forms.
The angles between
crystal faces are the
same as the angle of
another face, at the same
flat structure.
Structure of a
crystal
By
using an X-ray beam passing through a crystal breaks up into
many tiny beams to create a pattern of dots on a screen.
Physicists refer to this phenomenon as diffraction; it occurs
when waves interact with regularly spaced objects. So, atoms
within a crystal must be regularly spaced, and the spacing
must be comparable to the wavelength of X-rays.
Crystal structures are always symmetrical. Since
anions have extra electrons they tend to be bigger than cations, so in minerals with ionic bonding
cations tend to nestle snugly in the spaces between anions in many crystal structures so that as many
anions fit around a cation as there is room for.
Anion= negative charge --> extra electrons, so bigger
Cation= positive charge --> less electrons, so smaller
Same groups of atoms/ions/ionic molecules can be arranged in more than just one way. A mineral that
have the same chemical composition but different crystal structure is called a polymorph.
Formation of minerals
1) Solidification of a melt
2) Precipitation from a solution =atoms/molecules/ions dissolved in water bond together and sepearte
out of the water
3)Solid-state diffusion = the movement of atoms or ions through a solid to arrange into a new crystal
structure
4) Biomineralization= living organisms cause minerals to precipitate either within or on their bodies or
