Introduction Flashcards
1
Q
Source
A
A gem- producing country or area ,or a particular mine in that area
2
Q
Inorganic
A
Composed of ,or arising from ,non-living matter.
3
Q
Organic
A
Composed of, or arising form, non-living matter.
4
Q
Natural gems
A
Gems produced by natural processes, without human help .
Gems within the earth or from animals
5
Q
Atoms
A
The basic structural unit of all matter
6
Q
Chemical elements
A
A substance that consists of atoms of only one kind
7
Q
Chemical composition
A
Kinds and relative quantities of atoms that make up a material.
8
Q
Facet
A
A flash ,polished surface on a finished gem.
9
Q
Color gems
A
Chemical elements consist of only one kind of atom, and combinations of them make up .
10
Q
Red ruby
A
Chromium atoms
11
Q
Crystal
A
Aluminum and oxygen
12
Q
Emerald
A
Beryllium silicons, aluminum and oxygen atoms.
13
Q
Gems
A
Gems are minerals
14
Q
Being a gem
A
1: beautiful
2: durable
3: rare
15
Q
Mineral
A
A natural, inorganic substance with a characteristic chemical composition and usually characteristic structure.
16
Q
Rock
A
A natural material composed of masses of mineral crystals of one or more kinds.
Marble
Lapis lazuli : lazulite , calcite, pyrite
17
Q
Silicate
A
A mineral that contains the elements silicone and oxygen Quartz Beryl Garnet Tourmaline Jadeite Spodumene Opal
18
Q
Crystal structure
A
Regular, repeating internal arrangement of atoms in a material.
Crystal can be man made or natural
Most transparent gems are cut from one large crystal
Turquoise: many tiny cyclists
Lapis lazuli : mixture of different mineral crystals
19
Q
Amorphous
A
Lacking a regular crystal structure.
Amber
Opal
20
Q
Gem species
A
A broad gem category based on chemical composition and crystal structure.
Beryl made up beryllium, aluminium , oxygen and silicon atoms.
Zirconia: blue , green ,
Peridot: yellowish green or greenish yellow
21
Q
Gemologist classify gems into bored categories called species .
A
Spinal , zirconia , chrysoberyl, corundum
22
Q
Gem variety
A
A subcategory of species, based on color ,transparency or phenomena
Zirconia: blue , green ,
Peridot: yellowish green or greenish yellow
Aquarium most known blue variety
Emerald green
23
Q
Phenomenon
A
An unusual optical effect displayed by a gem
Star sapphire
Blue sheen moonstone
24
Q
Group
A
A family of gems from several closely related mineral species.
Garnet : almandine has iron .pyrope, contains magnesium. spessartine ,grossular and andradite .
Feldspar
Tourmaline
25
Most Colored Stone mining are small in scale , worked by individual miners who are working to feed their families.
Many colred Stones are mined by independent miners using small-scale mining methods.
26
Best selling colord Stones
Blue sapphire , Tanzanite, Ruby , emerald, cultured pearl , tourmaline, opal , amethyst and red garnet
27
Disclosure
Clearly and accurately informing customers about the nature of goods they buy
28
Treatment gem
Improves the marketability and availability of gems
29
Changing sources
Effect on gem's price , availability and popularity
30
Gemstone
Beautiful, rare ,durability and supply and demand
31
Rocks
The raw material of gemstone formation
32
Gems form
Right chemical
Right temperature
Extract them from earth
33
Geology
Science of earth
34
Sapphire
| Basalt
Rubi
| Marble
35
Crust
The surface and outermost layer of the earth .
| Thickness is7km to 40 km
36
Mantale
A layer between the earth's crust and its core
About 2.885 k.m
They are usually melted ,
37
Core
Beneath the mantle is core . The earth eaner layer . About 2,270
Mostly composed of iron, some nickel
38
Magma
General term for any molten rock
39
Plate
A section of the earth's rigid outer crust
40
Plate tectonics
Study of the formation, structure,and the movement of the plates of the earth's crust .
Plate tectonics explains the pattern of mountain rages, volcanoes, oceans and gem across the earth's surface.
41
Mantle convention
The circulation in the mantle that drives the movement of the earth's plates .
42
Mantle convection cusese
The opening of giant fissures in the earth's crust, in areas that geologists call speeding rigids. Best known is Mid-Atlantic Ridge
43
Producing the best gem formation
Depending on the part of the cycle that melts and recycles the earth's crust.
44
Subduction
A process that occurs when two of earth's plates collide,forcing one under the other . Best known is western coast of South America
45
Organic belt
Widespread area in the earth's crust where tectonics events cause major structural changes, often forming mountain range.
Himalayan mountain
46
Afghanistan and Pakistan
Emerald and rubies
47
Kashmir
Blue sapphire
48
Peridot and sapphire produced
When molten rock transport them from deep to crust
49
Corundum produced
Southeast Asia, Thailand, Vietnam and China are associated with volcanic rock
50
Rock cycling
Igneous
Metamorphic
Sedimentary
51
Igneous rock large one slow cooling
Small crystal rapid cooling
52
Igneous rock
Rock formed by crystallisation of molten material.
Granite : silicon, oxygen and aluminum continental crust Has large crystal
Topaz - tourmaline- spodumene
Basalt : iron and magnesium Oceanic crust
Tiny crystal
Peridot- doesn't produce the Gem
53
Metamorphic rock
Rock that have been altered by heat and ,pressure.
| Ruby- sapphire-garnet-lapis lazuli
54
Schist
Metamorphic rock with district alignment of mineral grain.
Zimbabwe , Brazil ,zambia ,Madagascar
Provide word's largest commercial emerald source
55
Sedimentary rock
Rock produced from the eroded and weathered remains of exciting rock.
Limestone, sandstone, quartz
Opal , malachite, turquoise
Sedimentary rock has one thing in common. The action of water.
Water goes through the rock and dissolve the mineral.the right action makes turquoise.
Although gems like ruby,sapphire,peridot and zircon are associated with volcanic rocks , scientists believe they come up from great depths as passenger
56
Moonstone
From igneous and type of feldspar, directly from volcanic rock. Best is from Sri lanka
57
Volcanic
Igneous activity at the earth surface, where magma erupts through a volcano or fissure.
58
Igneous formation
Volcanic
Pegmatites
Superheated water
59
Sapphires are weathered from basalt
Alkali basalt come from deeper level.
| The oceanic crust that be source .
60
Xenocryst
A foreign crystal that forms in unrelated rocks and brought to the surface as a passenger in magma.
Sapphire ... alkali
61
Pegmatite
An igneous rock formed from cooling, molten granite that follows fractures and its surrounding rock.
Granite have exotic elements lithium , beryllium, boron ,magnesium and fluoride
They are not become part of feldspar
Most important pegmatite source is Minas Gerais in Brazil which produces aquamarine- tourmaline
62
Pockets of gem mineral
The exotic elements crystal last, forming
63
Volatile
Exotic elements
64
Gem-bearing
Small present age of pegmatites are ...
tourmaline
Kunzite
Aquamarine
65
Vein
A mineral deposit that occupies fissures or fracture in the rock.
Amethyst, topaz emerald , Columbia, Brazil, imperial Topaz
66
Intrusion
Large mass of igneous rock that crystallizes underground without reaching the surface.
67
Superheated water
Transfer elements like beryllium and silicon and build a gem
68
Hydrothermal fluid
Hot, high pressure solution that can dissolve, transport and deposit minerals from one place to another.
69
Metamorphic formation
Regional metamorphic
Contact metamorphic
Metasomatic
70
Regional metamorphism
Changes in rock type and minerals over a wide area caused by heat and pressure of large scale geological event
71
Contact metamorphism
Where the magma meets the surrounding rock.
72
Metasomatism
A type of metamorphism where chemical changes in the minerals and rocks result from the introduction of material from external sources, often as hydrothermal solutions.
Chemical changes mineral rock .
Mozambique fine rubi
73
Sedimentary formation
Gems formed by water near earth's surface
| Geode formation
74
Geode formation
spherical, often hollow, mineral-lined cavity in rock.
Quartz
Amethyst
75
artisanal miners
An independent gem or mineral prospector who typically uses small-scale, nonmechanized recovery methods.
MRM Mozambique Montequez Ruby
Gem Fileds Zambian
76
Mining effected
```
Demand
Political climate
Labor cost
Environment
Accessibility
Deposit and mining methods
```
77
Overburden
The material covering a gem deposit that must be removed before production can begin.
Drill
Rotating spinal
Screw
78
Paleo channel
As ancient waterways changed direction over millions of years , they left dry and buried traces of those direction changes in so called
Mozambique MRM ruby
79
Ruby traps
High specific gravity collect at the bottom of depressions
80
Primary deposit
| Hard rock
```
Gems found in the rocks that they formed in
Columbian emerald
Paraiba tourmaline
Tanzanite
Pegmatite are important primary source
```
81
Drills help
Mine structure
| Supporting underground rock layer geology
82
Secondary deposit
```
Gems found away form their primary source
Mind first
Gem material are concentrated
Higher quality
Does not require costly equipment
Minas Gerais Brazil
Jadeite Myanmar
```
83
Alluvial
```
A deposit where gems are eroded from the source rock but remain in place close to the source.
Sapphire
Spinal
Tourmaline
Aquamarine
```
84
Eluvial deposit
A deposit where gems are eroded from the source rock but remain in place close to the source.
85
Placer
Workable alluvial deposit of gem minerals with economic potential.
Sir Lanka
Tanzania
86
Unit cell
The smallest group of atoms with characteristics chemical and chemical composition
87
Chemical elements Space for growth cooling time
Effect on shape size and color
88
Flux
Specific ingredients for synthetic crystal
89
Crystal form
Grow condition have to change - flux to cool - until the flux couldn't hold more ingredients
90
Nucleation
The atoms begin come together
91
If flux cool quickly
The rate of nucleation is higher - than the crystal growth so small crystal - high saturated flux so small crystal
92
If flux cool slowly
The rate of crystal growth is higher than the rate of nucleation so large crystal- less saturated bigger crystal
93
Aggregate
A mass of tiny crystal
94
Microcrystalline
An aggregate crystal visible under magnification
| Nephrite- jadeite- quartz
95
Cryptocrystalline
An aggregate only visible under high magnification
Chalcedony
Turquoise
96
Cubic
Diamonds
Garnet
Spinal
Fluoride
97
Tetragonal
Zircon
98
Trigonal
Rubi
Tourmaline
Quartz
99
Triclinic
Amazonite
Rhodonite
Feldspar
100
Hexagonal
Apatite
| Beryl
101
Orthorhombic
Tanzanite
Topaz
Period
102
Monoclinic
Spodgumene
103
Octahedron
Bigger cube
104
Dodecahedron
12 sided cube
105
Quartz
Oxygen- silicone
106
Emerald
```
Silicone
Oxygen
Aluminum
Beryllium
Chromium
```
107
Twinning
Change gem direction growth
108
Contact twin
Twinning crystal look likeone half - mirror image
109
Twinning plane
Location of a change in a crystal growth direction
110
Penetration twinning
Two crystal have grown through one another
Fluorite
Quartz
111
Cycling twinning
When twinning planes are not parallel and resulting in a wheel shapped crystal
112
Untwined
Polysynthetic
Lamellar twinning
When the rock formed and altered by pressure during metamorphism
113
Inclusion
A characteristic gemstone reaching its surface from the interior
114
Inclusion in emerald contain a liquid solid and a gas - needle
Inclusion in quartz contains mixers of water and petroleum
Moonstone inclusion called centipede
Lilypad inclusion found in peridot
Zebra stripes in amethyst
Ruby inclusion is finger prints
115
Liquid inclusion
Small pocket in gem filled with gas
116
Trace elements
Atoms aren't part of gems essential chemical composition
117
Sapphire
Aluminum +oxygen
| Iron and titanium are trace elements
118
Color zoning
If the quality of trace elements changed it lead to color zones and chang the color like sapphire needle
119
Habit
Shape and form of a mineral
120
Lapidary
Engraving
Cutting
Polishing
121
Tabular
Squat and flat like corundum
122
Prismatic
3-4-6-8-12 parallel faces
Aquamarine
Tourmaline
123
Euhedral
Well formed gem
124
Anhedral
Lacking face like the gems that been in river
125
Striation
Quartz and corundum horizontal or vertical
126
Pyramid
Equal triangular meet in a point
127
Bipyramid
Two pyramids back to back seen in sapphire
128
Density
How heavy an object is in relation to the size
129
Specific gravity (SG)
Ratio of the weight of material to the weight of an equal volume of water
130
Durability
Gemstone ability to withstand wear,heat and chemical
131
Hardness
Scratch
132
Toughness
Breaking and chipping
133
Mohs scale
```
Diamonds
Corundum
Topaz
Quartz
Feldspar
Apitie
Fluorite
Calcite
Gypsum
Talc
```
134
Cleavage
Flat break parallel to plane caused by weak or fewer bonds between atoms
135
Parting
Flat break parallel to a twinning plane
136
Conchoidal fracture
A curved extending from the surface inward
137
Stability
How gemstone resist light heat and old chemical
138
Thermal shock
Damage caused by sudden, exterm temperature change
139
Color is most important contribution
Desirability, marketability and value
140
Light
Is a form of radiant energy that travels in wave
141
Visible light
Is a small portion of the electromagnetic spectrum.
142
Wavelength
The distance between two high points of energy wave
143
Nanometers
Wavelengths are measured. NM
| One NM equals a millionth of a millimetre
144
Selective absorption
Process by which a material absorb some visible light and transmit others
145
Absorption spectrum
A pattern of dark vertical lines shown by certain gems when viewed through a spectroscope
146
White light
Combination of red,orange,yellow,green,blue and violet
147
Most gem color is caused by
Absorption which is influenced by chemical composition and crystal structure
148
Ultraviolet radiation and X-Ray are shorter wavelengths and higher energy
Longer wavelengths and lower energy like radio wave
149
Gem color
Interaction of electrons with visible light cause gem color
150
Every atoms
Have equal number of protons and electrons. Electron absorbing visible light and make the colour in jem
151
Losing electrons are called cation
Gaining electrons are called anion
152
Valences
Ion combining with other ion
153
Ground states
An electrons stable only at an energy level
154
Excited state
When electron absorb energy rises higher level
155
Transition
Movement from grand state to excited state
156
Period
Horizontal row in the periodic table and contain atomic number from low to high
157
Group
Arrange of electron in vortical line
158
Transition elements
Elements that absorb some wavelengths of visible light and produced colour in gem
159
Chromium
Cause red and green colour
160
Vanadium green
Cobalt blue
Iron green peridot
```
Chrome turmaline
Iron red garnet
Titanium blue in sapphire, spinal, kyanite,tourmaline
Nickel yellow sapphire
Coper Blue sapphire
Manganese red beryl , orange in garnet
Iron yellow pinkish sapphire
```
161
Valence shell
Outermost shell of an atom
162
Valence difference cause variations in colour intensity in the same gem
Crystal structure causing different colour in different gem
163
Allochromatic
A gem colour by trace elements like ruby and sapphire
164
Idiochromatic
A gem colored by its chemical composition like garnet and peridot
165
Change transfer
The movement of elections back and forth between ions , causing the selective absorption of light
166
Intervalence charge transfer
A process where two transaction elements with different valences exchange electrons to selectively absorb light Like aquamarine and sapphire
167
Treatment
Can alter color
168
Band gap
A constant energy difference
169
The high distance between valence band and conduction band
Make gem colour less like sapphire white
170
Color centre
A small defect in the crystal structure of a material that can absorb light and give rise
171
Irradiation
Exposing a gem to manmade radiation to change or improve its colour.
172
Fluorescence
Emission of visible light by material simulated by ultraviolet or X-Ray radiation ruby
173
Phosphorescence
Continued emission of visible light afterUV orX ray stop
174
Refraction
Chang speed and change direction of light travels from one material to another- diamond and garnet high compared quarters and opal
175
Doubling
An appearance of double image of gemstone like peridot
176
Double refraction
Gem crystal structure split into two different speed and direction like calcite
177
Single refraction
A gem crystal structure just absorb and refraction like diamonds, garnet and spinal
178
Optic axis
Direction of single or double refraction like zirconia
179
Pleochroism
Gem show different colour in different direction like tourmaline, sapphire, tanzanite, iolite
Dichroscope show .
180
Dispersion
The separation of white light into spectral colour. Garnet . Benitoite
181
Interference
Interaction between two light with same wavelength as travel along the same path
Phenomenal gem
Fine opal alexandrite and cat eye
182
Iridescence
A rainbow effect created when light broken up into spectral hues by thin layer like cultured pearls and mother of pearls
183
Diffraction
A special kind of interference phenomenon that produced patches of pure colour . Like opal or labradorite feldspar
